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#include <bits/stdc++.h> using namespace std; int a[100005], b[100005]; int main() { int i, j, n; scanf("%d", &n); for (i = 0; i < n; i++) scanf("%d", &a[i]), b[i] = a[i]; if (n <= 2) { puts("-1"); return 0; } sort(b, b + n); for (i = 0; i < n - 1; i++) { if (a[i] == a[i + 1]) continue; swap(a[i], a[i + 1]); for (j = 0; j < n && a[j] == b[j]; j++) ; if (j == n) { swap(a[i], a[i + 1]); continue; } for (j = 0; j < n && a[j] == b[n - j - 1]; j++) ; if (j == n) { swap(a[i], a[i + 1]); continue; } printf("%d %d\n", i + 1, i + 2); return 0; } puts("-1"); }
#include <bits/stdc++.h> using namespace std; bool solve() { int n; if (scanf("%d", &n) == EOF) return false; vector<int> x(n); int a[2] = {}; for (int i = 0; i < n; ++i) { scanf("%d", &x[i]); if (i && !a[0] && x[i - 1] > x[i]) a[0] = i; if (i && !a[1] && x[i - 1] < x[i]) a[1] = i; } for (int j = 0; j < 2; ++j) if (a[j]) { vector<int> x2 = x; swap(x2[a[j]], x2[a[j] - 1]); bool v1 = true, v2 = true; for (int i = 1; i < n; ++i) { v1 = v1 && x2[i] >= x2[i - 1]; v2 = v2 && x2[i] <= x2[i - 1]; } if (!v1 && !v2) { printf("%d %d\n", a[j], a[j] + 1); return true; } } printf("-1\n"); return true; } int main() { solve(); return 0; }
#include <bits/stdc++.h> using namespace std; bool unsrtd(int a[], int n) { int i; for (i = 1; i < n && a[i] >= a[i - 1]; i++) ; if (i == n) return false; for (i = 1; i < n && a[i] <= a[i - 1]; i++) ; if (i == n) return false; return true; } int main() { int n, mx, mn, mi, mni, i, j; scanf("%d", &n); int a[n]; for (i = 0; i < n; i++) scanf("%d", &a[i]); if (n < 3) { cout << -1 << endl; return 0; } for (i = 1; i < n; i++) if (a[i] != a[i - 1]) break; if (i == n) { cout << -1 << endl; return 0; } if (n == 3 && a[0] == a[n - 1] && a[0] != a[1]) { cout << -1 << endl; return 0; } for (i = 0; i < n; i++) { for (j = i + 1; j < n; j++) { if (a[j] != a[i]) { swap(a[i], a[j]); if (unsrtd(a, n)) { cout << i + 1 << " " << j + 1 << endl; return 0; } swap(a[i], a[j]); } } } return 0; }
#include <bits/stdc++.h> using namespace std; int N; int main() { cin >> N; vector<int> v(N), in(N), dc(N); for (int i = 0; i < N; ++i) scanf(" %d", &v[i]); in = dc = v; sort(in.begin(), in.end()); sort(dc.begin(), dc.end()); reverse(dc.begin(), dc.end()); for (int i = 0; i < N; i++) { for (int j = i + 1; j < N; j++) { if (v[i] == v[j]) continue; swap(v[i], v[j]); if (v != in && v != dc) return cout << i + 1 << " " << j + 1 << endl, 0; swap(v[i], v[j]); } for (int j = i + 1; j < N; j++) { if (v[i + 1] == v[j]) continue; swap(v[i + 1], v[j]); if (v != in && v != dc) return cout << i + 2 << " " << j + 1 << endl, 0; swap(v[i + 1], v[j]); } while (v[i + 1] == v[i] && i < N) i++; } puts("-1"); return 0; }
#include <bits/stdc++.h> using namespace std; int a[100005], b[100005]; bool desorden(int x, int y) { sort(b, b + 3); if (a[x] == a[y]) return false; swap(a[x], a[y]); bool ok = false; for (int i = 0; i < 3; i++) { if (a[i] != b[i]) ok = true; ; } if (ok) { for (int i = 0; i < 3; i++) { if (a[i] != b[3 - i - 1]) { return true; } } } swap(a[x], a[y]); return false; } int main() { int n; cin >> n; int x = -1, y = -1; int mayor = -1; for (int i = 0; i < n; i++) { cin >> a[i]; b[i] = a[i]; } for (int i = 1; i < n - 1; i++) { if (b[i] > mayor) { mayor = b[i]; x = i; } } if (a[0] > mayor) { x = 0; mayor = a[0]; } if (a[n - 1] > mayor) { x = n - 1; mayor = a[n - 1]; } int cant = 0; for (int i = 1; i < n - 1; i++) { if (a[i] != mayor) { y = i; break; } else { } } if (n == 3) { for (int i = 0; i < 3; i++) { for (int j = 0; j < 3; j++) { if (i != j && desorden(i, j)) { cout << i + 1 << " " << j + 1 << endl; return 0; } } } cout << -1 << endl; return 0; } if (n <= 2) { cout << -1 << endl; } else { if ((x != -1 && y != -1)) { cout << x + 1 << " " << y + 1 << endl; } else { if (a[0] != mayor) { cout << 1 << " " << 2 << endl; } else if (a[n - 1] != mayor) cout << n << " " << n - 1 << endl; else { cout << -1 << endl; } } } return 0; }
#include <bits/stdc++.h> using namespace std; int main() { int n; cin >> n; vector<int> v(n), a, b; for (int i = 0; i < n; i++) { cin >> v[i]; } a = v; b = v; sort(a.begin(), a.end()); sort(b.begin(), b.end(), greater<int>()); for (int i = 0; i < n - 1; i++) { if (v[i] != v[i + 1]) { swap(v[i], v[i + 1]); if (a == v || b == v) { swap(v[i], v[i + 1]); continue; } cout << i + 1 << " " << i + 2; return 0; } } cout << -1; return 0; }
#include <bits/stdc++.h> using namespace std; const int maxn = 100100; int n, a[maxn], b[maxn], c[maxn], d[maxn], sum, x, y; bool flag, h[maxn]; bool cmp(int a, int b) { return a > b; } int main() { scanf("%d", &n); for (int i = 0; i < n; i++) scanf("%d", &a[i]); if (n == 1 || n == 2) { cout << -1 << endl; return 0; } flag = true; for (int i = 1; i < n; i++) if (a[i] != a[i - 1]) { flag = false; break; } if (flag) { cout << -1 << endl; return 0; } memcpy(b, a, sizeof(a)); sort(b, b + n); memcpy(c, a, sizeof(a)); sort(c, c + n, cmp); if (n == 3 && a[0] == a[2]) { cout << -1 << endl; return 0; } sum = 0; memset(h, false, sizeof(h)); for (int i = 0; i < n; i++) if (a[i] != b[i]) d[sum++] = i; if (sum == 2) { h[d[0]] = true; h[d[1]] = true; } sum = 0; for (int i = 0; i < n; i++) if (a[i] != c[i]) d[sum++] = i; if (sum == 2) { h[d[0]] = true; h[d[1]] = true; } for (int i = 0; i < n; i++) if (!h[i]) { x = i; break; } for (int i = 0; i < n; i++) if (a[i] != a[x]) { y = i; break; } cout << x + 1 << ' ' << y + 1 << endl; return 0; }
#include <bits/stdc++.h> using namespace std; int main() { int i, j, k; int n, m; int a[100005]; while (scanf("%d", &n) != EOF) { for (i = 1; i <= n; i++) { scanf("%d", &a[i]); } int judge = 0; for (i = 1; i <= n - 2; i++) { if ((a[i] > a[i + 1] && a[i] > a[i + 2]) || (a[i] < a[i + 1] && a[i] < a[i + 2])) { printf("%d %d\n", i, i + 1); judge = 1; break; } else if ((a[i + 2] > a[i + 1] && a[i + 2] > a[i]) || (a[i + 2] < a[i + 1] && a[i + 2] < a[i])) { printf("%d %d\n", i + 1, i + 2); judge = 1; break; } else if (a[i] == a[i + 2] && a[i] != a[i + 1]) { if (a[i] < a[i + 1]) { if ((i != 1 && a[i - 1] < a[i + 1] || (i != n - 2) && a[i + 3] > a[i + 2])) { printf("%d %d\n", i, i + 1); judge = 1; break; } else if ((i != 1 && a[i - 1] > a[i] || (i != n - 2) && a[i + 3] < a[i + 1])) { printf("%d %d\n", i + 1, i + 2); judge = 1; break; } } else { if ((i != 1 && a[i - 1] > a[i + 1] || (i != n - 2) && a[i + 3] < a[i + 2])) { printf("%d %d\n", i, i + 1); judge = 1; break; } else if ((i != 1 && a[i - 1] < a[i] || (i != n - 2) && a[i + 3] > a[i + 1])) { printf("%d %d\n", i + 1, i + 2); judge = 1; break; } } } } if (judge == 0) printf("-1\n"); } }
#include <bits/stdc++.h> int a[111111], n, x, y; int max(int a, int b) { return (a > b) ? a : b; } int min(int a, int b) { return (a < b) ? a : b; } int ans() { int i, b, t, tt; if (n <= 2) return -1; if ((n == 3) && (a[1] == a[3])) return -1; b = 1; t = a[1]; for (i = 2; i <= n; i++) if (a[i] != t) { b = 0; break; } if (b == 1) return -1; b = 1; t = 0; tt = 0; for (i = 1; i < n; i++) { if ((t == 0) && (a[i] < a[i + 1])) t = i; if (a[i] > a[i + 1]) { tt = i; b = 0; break; } } if (b == 1) { x = t; y = t + 1; return 1; } else { if (t != 0) { if (a[t] == a[tt + 1]) { if (t == 1) { if (n == 3) { x = 1; y = 3; } else if (t + 1 != tt) { x = t; y = t + 1; } else if (a[tt + 1] != a[tt + 2]) { x = tt + 1; y = tt + 2; } else { x = tt; y = tt + 1; } } else { x = t; y = t + 1; } } else { x = t; y = tt + 1; } return 1; } } b = 1; t = 0; tt = 0; for (i = 1; i < n; i++) { if ((t == 0) && (a[i] > a[i + 1])) t = i; if (a[i] < a[i + 1]) { tt = i; b = 0; break; } } if (b == 1) { x = t; y = t + 1; return 1; } else { if (t != 0) { if (a[t] == a[tt + 1]) { if (t == 1) { if (n == 3) { x = 1; y = 3; } else if (t + 1 != tt) { x = t; y = t + 1; } else if (a[tt + 1] != a[tt + 2]) { x = tt + 1; y = tt + 2; } else { x = tt; y = tt + 1; } } else { x = t; y = t + 1; } } else { x = t; y = tt + 1; } return 1; } } } int main() { int i, j, t; scanf("%d", &n); for (i = 1; i <= n; i++) scanf("%d", &a[i]); if (ans() == -1) printf("%d\n", ans()); else printf("%d %d\n", x, y); return 0; }
#include <bits/stdc++.h> using namespace std; int main() { long long n, i, j, k, x, y, z, up = 0, down = 0, ux, uy, dx, dy; ux = uy = dx = dy = -1; cin >> n; long long a[n + 5]; bool f = 0; for (i = 0; i < n; i++) { cin >> a[i]; } if (n < 3) { cout << -1; return 0; } for (i = 0; i < n - 1; i++) { if (a[i] < a[i + 1]) { up++; if (up == 1) ux = i + 1, uy = i + 2; } else if (a[i] > a[i + 1]) { down++; if (down == 1) dx = i + 1, dy = i + 2; } } if (n == 3 && a[0] == a[2]) cout << -1; else if (up == 0 && down == 0) cout << -1; else if (down == 0) cout << ux << " " << uy; else if (up == 0) cout << dx << " " << dy; else if (down == 1 || up == 1) { if (dy == ux) { if (a[dy - 2] > a[dy - 1] && a[dy - 2] < a[dy]) cout << dy << " " << dy + 1; else if (a[uy - 1] > a[uy - 2] && a[uy - 1] < a[uy - 3]) cout << dx << " " << dy; else { if (dx == 1) cout << ux << " " << uy; else cout << dx << " " << dy; } } else { if (a[dy - 1] > a[ux - 1] && a[dy - 1] < a[dx - 1]) cout << ux << " " << uy; else if (a[ux - 1] > a[dy - 1] && a[ux - 1] < a[uy - 1]) cout << dx << " " << dy; else { if (ux == 1) cout << dx << " " << dy; else cout << ux << " " << uy; } } } else cout << ux << " " << uy; }
#include <bits/stdc++.h> using namespace std; bool cmp(int a, int b) { return (a > b); } int main() { vector<int> arr; vector<int> a; vector<int> b; int n, i, f = 0; cin >> n; for (i = 0; i < n; i++) { int x; cin >> x; arr.push_back(x); a.push_back(x); b.push_back(x); } sort(a.begin(), a.end(), cmp); sort(b.begin(), b.end()); for (i = 1; i < n; i++) if (arr[i] != arr[i - 1] && (!((arr[i] == a[i - 1] && arr[i - 1] == a[i]) || (arr[i] == b[i - 1] && arr[i - 1] == b[i])))) { cout << i << " " << i + 1 << endl; return 0; } cout << "-1" << endl; return 0; }
#include <bits/stdc++.h> using namespace std; int main() { ios::sync_with_stdio(0); cin.tie(0); int n; cin >> n; int ar[n]; for (int i = 0; i < n; i++) { cin >> ar[i]; } set<int> prov(ar, ar + n); if (prov.size() <= 1 || n <= 2) { cout << -1; return 0; } if (ar[0] > ar[n - 1]) { for (int i = 1; i < n - 1; i++) { if (ar[i] < ar[0]) { cout << "1 " << i + 1; return 0; } else if (ar[i] > ar[n - 1]) { cout << i + 1 << " " << n; return 0; } } } else if (ar[0] < ar[n - 1]) { for (int i = 1; i < n - 1; i++) { if (ar[i] > ar[0]) { cout << "1 " << i + 1; return 0; } else if (ar[i] < ar[n - 1]) { cout << i + 1 << " " << n; return 0; } } } else { if (n == 3) { cout << -1; return 0; } else { for (int i = 2; i < n - 1; i++) { if (ar[1] != ar[i]) { cout << "2 " << i + 1; return 0; } } } } cout << -1; }
#include <bits/stdc++.h> using namespace std; bool ISPRIME(int n) { if (n % 2 == 0) return false; for (int i = 2; i * i <= n; i++) { if (n % i == 0) return false; } return true; } int main() { long long unsigned m[110000], n, cnt = 0, cnt1 = 0; bool j = false; int r; int v = 0; cin >> n; for (int r1 = 0; r1 < n; r1++) cin >> m[r1]; if (n == 1 || n == 2) { cout << -1; return 0; } for (r = 0; r < n - 1; r++) { if (m[r] != m[r + 1]) { swap(m[r], m[r + 1]); j = true; for (int r2 = 0; r2 < n - 1; r2++) { if (m[r2] <= m[r2 + 1]) { cnt++; if (cnt >= n - 1) { j = false; cnt = 0; swap(m[r], m[r + 1]); } } } for (int r3 = 0; r3 < n - 1; r3++) { if (m[r3] >= m[r3 + 1]) { cnt1++; if (cnt1 >= n - 1) { j = false; cnt1 = 0; swap(m[r], m[r + 1]); } } } } cnt = cnt1 = 0; if (j) { cout << r + 1 << ' ' << r + 2; return 0; } } cout << -1; return 0; }
#include <bits/stdc++.h> using namespace std; int main() { ios_base::sync_with_stdio(false); cin.tie(NULL); long long int n; cin >> n; vector<long long int> a, b, c; long long int x; for (long long int i = 0; i < n; i++) { cin >> x; a.push_back(x); } b = c = a; sort(b.begin(), b.end()); sort(c.rbegin(), c.rend()); for (int i = 1; i < n; i++) { if (a[i] != a[i - 1]) { swap(a[i], a[i - 1]); if (a == b || a == c) { swap(a[i], a[i - 1]); continue; } cout << i << " " << i + 1 << endl; return 0; } } cout << -1 << endl; }
#include <bits/stdc++.h> using namespace std; int n, m, minn, maxn, sum; map<int, int> q; int a[111111]; int main() { minn = 0; maxn = 0; cin >> n; sum = 0; for (int i = 1; i <= n; i++) { cin >> a[i]; if (!minn || a[i] < a[minn]) minn = i; if (!maxn || a[i] > a[maxn]) maxn = i; if (q[a[i]] == 0) sum++; q[a[i]]++; } if (sum == 1) cout << -1 << endl; else { int tmp = 0; for (int i = 1; i <= n; i++) if (a[i] != a[minn] && (!tmp || a[tmp] == a[maxn])) tmp = i; if (a[tmp] != a[maxn] && a[tmp] != a[1]) cout << 1 << " " << tmp << endl; else if (a[tmp] != a[maxn] && a[tmp] != a[n]) cout << tmp << " " << n << endl; else if (a[tmp] != a[maxn]) cout << minn << " " << maxn << endl; else { for (int i = 1; i <= n - 2; i++) { if (a[i] == a[minn] && a[i + 1] == a[maxn] && a[i + 1] == a[i + 2] || a[i] == a[maxn] && a[i + 1] == a[minn] && a[i + 1] == a[i + 2]) { cout << i << " " << i + 1 << endl; return 0; } if (a[i] == a[minn] && a[i + 1] == a[minn] && a[i + 1] != a[i + 2] || a[i] == a[maxn] && a[i + 1] == a[maxn] && a[i + 1] != a[i + 2]) { cout << i + 1 << " " << i + 2 << endl; return 0; } } if (n > 3) cout << "1 2" << endl; else cout << -1 << endl; } } return 0; }
#include <bits/stdc++.h> using namespace std; const int maxn = 1000 * 100 + 100; int n, a[maxn], t = 0, p = -1, q = -1; int main() { cin >> n; for (int i = 0; i < n; i++) cin >> a[i]; if (n < 3 || (n == 3 && a[0] == a[2])) { cout << -1 << endl; return 0; } for (int i = 1; i < n; i++) if (a[i] != a[0]) t = 1; if (t == 0) { cout << -1 << endl; return 0; } for (int i = 1; i < n; i++) { if (a[i] > a[0]) p = i; if (a[i] < a[0]) q = i; } if (p == -1 || q == -1) { if (p == -1) { for (int i = 0; i < n; i++) a[i] *= -1; swap(q, p); } for (int i = 1; i < p; i++) if (a[i] != a[0]) { cout << 1 << " " << i + 1 << endl; return 0; } int tmin = n - 1, mmax = a[n - 1]; for (int i = n - 2; i >= 1; i--) { if (a[i] < mmax) { cout << i + 1 << " " << tmin + 1 << endl; return 0; } else { mmax = a[i]; tmin = i; } } if (a[2] != a[0]) cout << 1 << " " << 2 << endl; else cout << 2 << " " << 3 << endl; return 0; } if (p > q) { cout << 1 << " " << p + 1 << endl; } else { cout << 1 << " " << q + 1 << endl; } return 0; }
#include <bits/stdc++.h> using namespace std; const int N = 100010; int n, a[N], b[N], c[N], d1[N], d2[N]; int main(int argc, char **argv) { scanf("%d", &n); for (int i = 0; i < n; ++i) { scanf("%d", a + i); b[i] = c[i] = a[i]; } sort(b, b + n); sort(c, c + n, greater<int>()); for (int i = 0; i < n; ++i) { if (b[i] != a[i]) d1[i] = 1; if (c[i] != a[i]) d2[i] = 1; } for (int i = 1; i < n; ++i) { d1[i] += d1[i - 1]; d2[i] += d2[i - 1]; } for (int t, tt, x, y, X, Y, XX, YY, i = 1; i < n; ++i) { if (a[i] != a[i - 1]) { x = a[i - 1]; y = a[i]; X = b[i - 1]; Y = b[i]; XX = c[i - 1]; YY = c[i]; t = tt = 0; if (x == X && y != X) ++t; if (x != X && y == X) --t; if (y == Y && x != Y) ++t; if (y != Y && x == Y) --t; if (x == XX && y != XX) ++tt; if (x != XX && y == XX) --tt; if (y == YY && x != YY) ++tt; if (y != YY && x == YY) --tt; if (d1[n - 1] + t != 0 && d2[n - 1] + tt != 0) { cout << i << " " << i + 1 << endl; return 0; } } } cout << -1 << endl; return 0; }
#include <bits/stdc++.h> using namespace std; bool sip; int A[100005], ctos, lleva = 0, U[5], D[5], uno = 1, dos = 0, unoes, doses, unop, dosp; map<int, int> M; int main() { scanf("%d", &ctos); for (int i = 1; i <= ctos; i++) { scanf("%d", &A[i]); } for (int i = 1; i <= ctos; i++) { if (M.size() < 3) { M[A[i]] = i; } } if (M.size() < 3) { if (M.size() == 2) { if (ctos <= 10) { for (int a = 1; a <= ctos; a++) { for (int b = a + 1; b <= ctos; b++) { if (A[a] == A[b]) { continue; } swap(A[a], A[b]); sip = true; for (int i = 1; i < ctos; i++) { if (A[i] > A[i + 1]) { sip = false; break; } } if (sip) { swap(A[a], A[b]); continue; } sip = true; for (int i = 1; i < ctos; i++) { if (A[i] < A[i + 1]) { sip = false; break; } } if (sip) { swap(A[a], A[b]); continue; } else { printf("%d %d\n", a, b); return 0; } } } printf("-1\n"); } else { unoes = A[1]; for (int i = 2; i <= ctos; i++) { if (A[i] == A[1]) { uno++; } else { doses = A[i]; ++dos; } } if (dos > uno) { swap(unoes, doses); } for (int i = 1; i <= ctos; i++) { if (A[i] == unoes) { for (int e = i + 1; e <= ctos; e++) { if (A[e] == unoes) { for (int d = 1; d <= ctos; d++) { if (A[d] == doses) { printf("%d %d\n", min(e, d), max(e, d)); return 0; } } } } } } } } else { printf("-1\n"); } } else { for (map<int, int>::iterator i = M.begin(); lleva < 3; i++) { ++lleva; U[lleva] = i->first; D[lleva] = i->second; } for (int i = 1; i <= 3; i++) { for (int e = 1; e < 3; e++) { if (D[e + 1] < D[e]) { swap(D[e + 1], D[e]); swap(U[e + 1], U[e]); } } } for (int a = 1; a <= 3; a++) { for (int b = a + 1; b <= 3; b++) { for (int c = 1; c <= 3; c++) { if (c == a or c == b) continue; swap(U[a], U[b]); if (!((U[1] <= U[2] and U[2] <= U[3]) or (U[1] >= U[2] and U[2] >= U[3]))) { printf("%d %d\n", min(D[a], D[b]), max(D[a], D[b])); return 0; } swap(U[a], U[b]); } } } printf("-1\n"); } return 0; }
#include <bits/stdc++.h> using namespace std; int a[100001], b[100001]; int n; void solve() { int i, x, y, z; sort(b, b + n); if (b[0] == b[n - 1] || n <= 2) { cout << -1 << endl; return; } x = 0; y = 1; z = -1; for (i = 2; i < n; i++) if (a[x] != a[i] || a[y] != a[i]) { z = i; break; } if (z == -1) { cout << -1 << endl; return; } if (a[x] == a[z]) { x = y; y = z; z++; while (z < n && a[x] == a[z]) z++; if (z == n) { cout << -1 << endl; return; } } if (a[x] == a[y]) { cout << y + 1 << " " << z + 1 << endl; return; } if (a[y] == a[z]) { cout << x + 1 << " " << y + 1 << endl; return; } if ((a[x] < a[y] && a[y] < a[z]) || (a[z] < a[y] && a[y] < a[x])) { cout << y + 1 << " " << z + 1 << endl; return; } cout << x + 1 << " " << z + 1 << endl; } void input() { int i; while (cin >> n) { for (i = 0; i < n; i++) cin >> a[i], b[i] = a[i]; solve(); } } int main() { input(); return 0; }
#include <bits/stdc++.h> using namespace std; int sorted(int a[100001], int n) { int l = 0, i, s = 0; int b[100001] = {0}; for (i = 0; i < n; i++) b[i] = a[i]; sort(b, b + n); for (i = 0; i < n; i++) { if (a[i] != b[i]) { l = 0; break; } l++; } if (l != n) { s = 0; for (i = n - 1; i >= 0; i--) { if (a[s] != b[i]) { return 0; } s++; } } return 1; } int main() { int n, m, i, j, k, a, b, c[100001], l = 1; scanf("%d", &n); for (i = 0; i < n; i++) { scanf("%d", &c[i]); if (c[i] == b && i != 0) { l++; } else if (c[i] != b && i != 0) { l = 0; } b = c[i]; } if (l == n || n == 1 || n == 2) { printf("-1\n"); return 0; } int x; for (i = 0; i < n; i++) { for (j = 0; j < n; j++) { if (i != j && c[i] != c[j]) { swap(c[i], c[j]); x = sorted(c, n); if (x == 1) { swap(c[i], c[j]); continue; } printf("%d %d\n", i + 1, j + 1); return 0; } } } printf("-1\n"); return 0; }
#include <bits/stdc++.h> int n; int as[100002]; int num1[100002]; int num2[100002]; int stcheck(void) { int flg = 1; for (int i = 1; i < n; i++) if (as[i] > as[i - 1]) flg = 0; if (flg) return 0; flg = 1; for (int i = 1; i < n; i++) if (as[i] < as[i - 1]) flg = 0; if (flg) return 0; return 1; } int main() { int vl[3]; int pls[3]; scanf("%d", &n); for (int i = 0; i < n; i++) scanf("%d", &as[i]); vl[0] = -1; vl[1] = -1; vl[2] = -1; int dsum = 0; for (int i = 0; i < n; i++) { int flg = 1; for (int j = 0; j < dsum; j++) { if (vl[j] == as[i]) flg = 0; } if (flg) { if (dsum < 3) { vl[dsum] = as[i]; pls[dsum] = i; dsum++; } } } if (dsum == 3) { for (int i = 0; i < 3; i++) { for (int j = i + 1; j < 3; j++) { int kvl = as[pls[i]]; as[pls[i]] = as[pls[j]]; as[pls[j]] = kvl; if (stcheck()) { printf("%d %d\n", pls[i] + 1, pls[j] + 1); return 0; } kvl = as[pls[i]]; as[pls[i]] = as[pls[j]]; as[pls[j]] = kvl; } } } if (dsum == 2) { int nk1 = 0; int nk2 = 0; for (int i = 0; i < n; i++) { if (as[i] == vl[0]) { num1[nk1] = i; nk1++; } else { num2[nk2] = i; nk2++; } } if (nk1 > 2) { printf("%d %d\n", num1[1] + 1, num2[0] + 1); return 0; } if (nk2 > 2) { printf("%d %d\n", num2[1] + 1, num1[0] + 1); return 0; } for (int i = 0; i < n; i++) { for (int j = i + 1; j < n; j++) { if (as[i] != as[j]) { int kvl = as[i]; as[i] = as[j]; as[j] = kvl; if (stcheck()) { printf("%d %d\n", i + 1, j + 1); return 0; } kvl = as[i]; as[i] = as[j]; as[j] = kvl; } } } } printf("-1\n"); return 0; }
#include <bits/stdc++.h> using namespace std; int a[(int)1e5 + 3]; int main() { int n; scanf("%d", &n); for (int i = 0; i < n; i++) { scanf("%d", &a[i]); } int cur = a[0], pl = -1; for (int i = 1; i < n; i++) { if (cur != a[i]) { pl = i; break; } } if (n == 1 || n == 2 || pl == -1 || (n == 3 && a[0] == a[n - 1])) { printf("-1"); } else { int i = pl + 1; a[n] = -1; while (a[i] == a[0]) ++i; if (pl == n - 1) { printf("%d %d", n - 1, n); return 0; } if (a[pl] == a[pl + 1]) { printf("%d %d", pl, pl + 1); return 0; } if (i == n) { if (pl == 1) { printf("%d %d", pl + 1, pl + 2); } else { printf("%d %d", pl, pl + 1); } return 0; } if (a[0] < a[pl]) { if (a[i] > a[pl]) { printf("%d %d", pl, pl + 1); } else { if (a[i] < a[0]) printf("%d %d", pl + 1, pl + 2); else printf("%d %d", pl, pl + 1); } } else { if (a[i] < a[pl]) { printf("%d %d", pl + 1, pl + 2); } else { if (a[i] > a[0]) printf("%d %d", pl + 1, pl + 2); else printf("%d %d", pl, pl + 1); } } } return 0; }
#include <bits/stdc++.h> using namespace std; void scanint(long long int &x); int main() { ios_base::sync_with_stdio(false); cin.tie(NULL); long long int n; scanint(n); long long int a[n]; long long int i = 0; long long int j = 0; long long int unq; vector<long long int> v1, v2; for (i = 0; i < n; i++) scanint(a[i]), v1.push_back(a[i]), v2.push_back(a[i]); sort(v1.begin(), v1.end()); sort(v2.begin(), v2.end(), greater<long long int>()); bool f = true; bool b = true; for (i = 0; i < n - 1; i++) { if (a[i] != a[i + 1]) { swap(a[i], a[i + 1]); f = true; b = true; for (j = 0; j < n; j++) { if (a[j] != v1[j]) f = false; if (a[j] != v2[j]) b = false; if (!f && !b) { cout << i + 1 << " " << i + 2 << endl; return 0; } } swap(a[i], a[i + 1]); } } cout << -1 << endl; return 0; } void scanint(long long int &x) { register int c = getchar(); x = 0; int neg = 0; for (; ((c < 48 || c > 57) && c != '-'); c = getchar()) ; if (c == '-') { neg = 1; c = getchar(); } for (; c > 47 && c < 58; c = getchar()) { x = (x << 1) + (x << 3) + c - 48; } if (neg) x = -x; }
#include <bits/stdc++.h> using namespace std; long long a[200006], b[200006], c[200006]; long long n; bool check() { bool ok = 0, ok1 = 0; for (long long i = 0; i < n; i++) { if (a[i] != b[i]) { ok = 1; break; } } for (long long i = 0; i < n; i++) { if (a[i] != c[i]) { ok1 = 1; break; } } if (ok == 1 && ok1 == 1) return true; return false; } void solve() { cin >> n; for (long long i = 0; i < n; i++) { cin >> a[i]; b[i] = a[i]; c[i] = a[i]; } sort(b, b + n); sort(c, c + n, greater<long long>()); for (long long i = 1; i < n; i++) { if (a[i] != a[i - 1]) { swap(a[i], a[i - 1]); bool ok = check(); if (ok == true) { cout << i << " " << i + 1 << endl; return; } swap(a[i], a[i - 1]); } } cout << "-1" << endl; } int main() { ios_base::sync_with_stdio(false); cin.tie(NULL); cout.tie(NULL); long long t = 1; while (t--) solve(); return 0; }
#include <bits/stdc++.h> using namespace std; const int N = 1e5 + 20; int n, i, x; vector<int> a, b, c; int main() { scanf("%d", &n); for (i = 0; i < n; i++) scanf("%d", &x), a.push_back(x); c = b = a; sort(b.begin(), b.end()); sort(c.rbegin(), c.rend()); for (i = 1; i < n; i++) { if (a[i] != a[i - 1]) { swap(a[i], a[i - 1]); if (a != b && c != a) { printf("%d %d", i, i + 1); return 0; } swap(a[i], a[i - 1]); } } printf("-1"); return 0; }
#include <bits/stdc++.h> using namespace std; const int INF = INT_MAX; const long long INFL = LLONG_MAX; const int output_precision = 15; const bool debug = true; int mn, mx, N, A[100100]; int main() { ios_base::sync_with_stdio(0); cout.precision(output_precision); cout << fixed; cout.tie(0); cin >> N; for (int(i) = 1, j1234 = N; (i) <= j1234; (i)++) cin >> A[i]; if (N <= 2) { cout << -1 << '\n'; return 0; } int identical = 1; for (int(i) = 1, j1234 = N; (i) <= j1234; (i)++) identical &= A[1] == A[i]; if (identical) { cout << -1 << '\n'; return 0; } if (N <= 30) { for (int(i) = 1, j1234 = N; (i) <= j1234; (i)++) for (int(j) = 1, j1234 = N; (j) <= j1234; (j)++) if (i < j && A[i] != A[j]) { swap(A[i], A[j]); int sorted = 1; for (int(ii) = 1, j1234 = N - 1; (ii) <= j1234; (ii)++) sorted &= A[ii] <= A[ii + 1]; if (sorted) { swap(A[i], A[j]); continue; } sorted = 1; for (int(ii) = 1, j1234 = N - 1; (ii) <= j1234; (ii)++) sorted &= A[ii] >= A[ii + 1]; if (sorted) { swap(A[i], A[j]); continue; } cout << i << " " << j << '\n'; return 0; } } else { for (int i = 1; i <= N - 1; i++) { if (A[i] == A[i + 1]) continue; swap(A[i], A[i + 1]); int sorted = 1; for (int ii = i - 1; ii <= i + 1; ii++) if (1 <= ii && ii + 1 <= N) sorted &= A[ii] <= A[ii + 1]; if (sorted) { swap(A[i], A[i + 1]); continue; } sorted = 1; for (int ii = i - 1; ii <= i + 1; ii++) if (1 <= ii && ii + 1 <= N) sorted &= A[ii] >= A[ii + 1]; if (sorted) { swap(A[i], A[i + 1]); continue; } cout << i << " " << i + 1 << '\n'; return 0; } } cout << -1 << '\n'; return 0; }
#include <bits/stdc++.h> using namespace std; int N; vector<int> v; bool isSorted() { bool ok1 = true; for (int i = 1; i < N; i++) if (v[i] > v[i - 1]) { ok1 = false; break; } bool ok2 = true; for (int i = 1; i < N; i++) if (v[i] < v[i - 1]) { ok2 = false; break; } return ok1 || ok2; } int main() { scanf("%d\n", &N); for (int i = 0; i < N; i++) { int x; scanf("%d", &x); v.push_back(x); } if (N <= 2) { printf("-1\n"); return 0; } for (int i = 0; i < N - 1; i++) { bool ok = false; for (int j = i + 1; j < N; j++) if (v[i] != v[j]) { ok = true; int aux = v[i]; v[i] = v[j]; v[j] = aux; if (!isSorted()) { printf("%d %d\n", i + 1, j + 1); return 0; } aux = v[i]; v[i] = v[j]; v[j] = aux; } if (!ok) break; } printf("-1\n"); return 0; }
#include <bits/stdc++.h> int main() { int a[100000], b[100000], c[100000], n, tmp = 0; scanf("%d", &n); for (int i = 0; i < n; ++i) { scanf("%d", &a[i]); b[i] = a[i]; c[i] = a[i]; } std::sort(b, b + n, std::greater<int>()); std::sort(c, c + n, std::less<int>()); for (int i = 1; i < n; ++i) if (a[i] == a[i - 1]) ++tmp; if (tmp == n - 1) { printf("%d", -1); return 0; } for (int i = 0; i < n; ++i) for (int j = i + 1; j < n; ++j) if (a[i] != a[j]) { std::swap(a[i], a[j]); if (!std::equal(a, a + n, b) && !std::equal(a, a + n, c)) { printf("%d %d", i + 1, j + 1); return 0; } std::swap(a[i], a[j]); } printf("%d", -1); }
#include <bits/stdc++.h> int gcd(int a, int b) { return b == 0 ? a : gcd(b, a % b); } int lcm(int a, int b) { return ((a * b) / gcd(a, b)); } using namespace std; bool cmp(int a, int b) { return a > b; } int main() { int a, b, c, i, j, k, tc, t; int n, m, cnt = 0; int eq = 1; int ara[100005]; vector<int> vec, vec2, vec3; cin >> n; for (i = 0; i < n; i++) { scanf("%d", &ara[i]); vec.push_back(ara[i]); if (i != 0) { if (ara[i] != ara[i - 1]) eq = 0; } } if (n <= 2 || eq) { printf("-1"); } else { vec2 = vec3 = vec; sort(vec2.begin(), vec2.end()); sort(vec3.begin(), vec3.end(), cmp); int flg = 0; for (i = 1; i < n; i++) { if (ara[i] != ara[0]) { if (i == n - 1) { continue; } swap(vec[i], vec[0]); if (vec == vec2 || vec == vec3) { swap(vec[i], vec[0]); if (i - 1 > 0) { swap(vec[i], vec[i - 1]); if (vec != vec2 && vec != vec3) { printf("%d %d\n", i, i + 1); return 0; } swap(vec[i], vec[i - 1]); } continue; } printf("%d %d\n", 1, i + 1); return 0; } } for (i = n - 2; i >= 0; i--) { if (ara[i] != ara[n - 1]) { if (i == 0) { printf("-1\n"); return 0; } swap(vec[i], vec[n - 1]); if (vec == vec2 || vec == vec3) { swap(vec[i], vec[n - 1]); swap(vec[i], vec[i + 1]); if (vec != vec2 && vec != vec3) { printf("%d %d", i + 1, i + 2); return 0; } swap(vec[i], vec[i + 1]); continue; } printf("%d %d\n", i + 1, n); return 0; } } printf("-1"); } return 0; }
#include <bits/stdc++.h> using namespace std; int arr[100005]; int main() { int n, i, j; scanf("%d", &n); for (i = 0; i < n; i++) scanf("%d", &arr[i]); int flag = 0; for (i = 1; i < n; i++) { if (arr[i] != arr[i - 1]) { flag = 1; break; } } if (flag == 0) { printf("-1\n"); return 0; } flag = 0; int k; int temp; for (i = 0; i < n; i++) { for (j = i + 1; j < n; j++) { if (arr[i] != arr[j]) { temp = arr[i]; arr[i] = arr[j]; arr[j] = temp; for (k = 2; k < n; k++) { if ((arr[k - 1] < arr[k] && arr[k - 1] < arr[k - 2]) || (arr[k - 1] > arr[k] && arr[k - 1] > arr[k - 2])) { printf("%d %d\n", i + 1, j + 1); return 0; } } temp = arr[i]; arr[i] = arr[j]; arr[j] = temp; } } } printf("-1\n"); return 0; }
#include <bits/stdc++.h> using namespace ::std; int num[100001], n; bool asc, desc; int main() { scanf("%d", &n); for (int i = 0; i < n; i++) scanf("%d", &num[i]); for (int i = 0; i < n - 1; i++) { if (num[i] == num[i + 1]) continue; swap(num[i], num[i + 1]); asc = desc = true; for (int j = 0; j < n - 1 && (asc || desc); j++) asc = asc && num[j] <= num[j + 1], desc = desc && num[j] >= num[j + 1]; if (!asc && !desc) { printf("%d %d\n", i + 1, i + 2); return 0; } swap(num[i], num[i + 1]); } printf("-1\n"); return 0; }
#include <bits/stdc++.h> using namespace std; vector<long long> vec, a, b; int main() { int n; cin >> n; for (int i = 0; i < n; i++) { int x; cin >> x; vec.push_back(x); a.push_back(x); b.push_back(x); } sort(a.begin(), a.end()); sort(b.rbegin(), b.rend()); for (int i = 1; i < n; i++) { if (vec[i] != vec[i - 1]) { swap(vec[i], vec[i - 1]); { if (vec != a && vec != b) { cout << i << " " << i + 1 << endl; return 0; } } swap(vec[i], vec[i - 1]); } } cout << "-1" << endl; return 0; }
#include <bits/stdc++.h> using namespace std; int n, a[1000005], r[3], cnt; bool up, down; set<int> s; int main() { srand(75435); scanf("%d", &n); for (int i = 0; i < n; i++) scanf("%d", &a[i]); if (n <= 2) { cout << -1; return 0; } for (int i = 0; i < n; i++) { if (s.find(a[i]) == s.end()) { if (cnt < 3) r[cnt++] = i; s.insert(a[i]); } } if (cnt == 3) { if (r[0] > r[1]) swap(r[0], r[1]); if (r[0] > r[2]) swap(r[0], r[2]); if (r[1] > r[2]) swap(r[1], r[2]); if ((a[r[1]] > a[r[0]] && a[r[1]] > a[r[2]]) || (a[r[1]] < a[r[0]] && a[r[1]] < a[r[2]])) { cout << r[0] + 1 << ' ' << r[2] + 1; return 0; } cout << r[0] + 1 << ' ' << r[1] + 1 << endl; return 0; } for (int i = 0; i < n - 1; i++) if (a[i] != a[i + 1]) { swap(a[i], a[i + 1]); up = true; down = true; for (int j = 0; j < n - 1; j++) if (a[j] > a[j + 1]) up = false; else if (a[j] < a[j + 1]) down = false; if (!down && !up) { cout << i + 1 << ' ' << i + 2; return 0; } swap(a[i], a[i + 1]); } cout << -1; return 0; }
#include <bits/stdc++.h> using namespace std; long long n, a[1000 * 100 + 100]; bool so() { for (long long i = 1; i < n; i++) if (a[i] > a[i + 1]) return false; return true; } bool nou() { for (long long i = 1; i < n; i++) if (a[i] < a[i + 1]) return false; return true; } int main() { ios_base::sync_with_stdio(false); cin >> n; for (long long i = 1; i <= n; i++) { cin >> a[i]; } for (int i = 1; i < n; i++) if (a[i] != a[i + 1]) { swap(a[i], a[i + 1]); if (!(nou() || so())) { cout << i << " " << i + 1; return false; } swap(a[i], a[i + 1]); } cout << -1; return false; }
#include <bits/stdc++.h> using namespace std; void out(int a, int b) { cout << a + 1 << " " << b + 1 << endl; exit(0); } int main() { int n; cin >> n; vector<int> a(n); for (auto &ai : a) cin >> ai; if (n <= 2) return !(cout << -1 << endl); for (int i = 1; i + 1 < n; i++) if (a[i - 1] != a[i + 1]) { if (a[i - 1] == a[i]) out(i, i + 1); if (a[i] == a[i + 1]) out(i - 1, i); if (a[i - 1] > a[i] && a[i] > a[i + 1]) out(i, i + 1); if (a[i - 1] < a[i] && a[i] < a[i + 1]) out(i - 1, i); if (a[i - 1] < a[i] && a[i] > a[i + 1]) out(i - 1, i + 1); if (a[i - 1] > a[i] && a[i] < a[i + 1]) out(i - 1, i + 1); } if (a[0] == a[1] || n == 3) return !(cout << -1 << endl); out(0, 1); return 0; }
#include <bits/stdc++.h> using namespace std; static const double EPS = 1e-5; int main() { int n; cin >> n; vector<pair<int, int> > vec; vector<pair<int, int> > vec2; int ma = 0; int mi = INT_MAX; for (int i = 0; i < n; i++) { int tmp; cin >> tmp; ma = max(ma, tmp); mi = min(mi, tmp); vec.push_back(make_pair(tmp, i + 1)); } if (ma == mi) { cout << -1 << endl; return 0; } if (n <= 2) { cout << -1 << endl; return 0; } if (n == 3) { if (vec[0].first == vec[2].first) { cout << -1 << endl; return 0; } if (abs(vec[1].first - vec[0].first) > abs(vec[1].first - vec[2].first)) { cout << 1 << " " << 2 << endl; return 0; } else { cout << 2 << " " << 3 << endl; return 0; } } for (int i = 0; i + 3 < n; i++) { int array[4]; array[0] = vec[i].first; array[1] = vec[i + 1].first; array[2] = vec[i + 2].first; array[3] = vec[i + 3].first; if (array[0] == array[1] && array[1] == array[2] && array[2] == array[3]) continue; for (int j = 0; j <= 3; j++) { for (int k = 0; k <= 3; k++) { if (j == k) continue; if (array[j] == array[k]) continue; swap(array[j], array[k]); bool up = false; bool down = false; for (int p = 0; p <= 2; p++) { if (array[p + 1] - array[p] > 0) { if (down == true) { cout << vec[i + j].second << " " << vec[i + k].second << endl; return 0; } up = true; } if (array[p + 1] - array[p] < 0) { if (up == true) { cout << vec[i + j].second << " " << vec[i + k].second << endl; return 0; } down = true; } } swap(array[j], array[k]); } } } return 0; }
#include <bits/stdc++.h> using namespace std; int main(void) { int n; scanf("%d", &n); int v[n]; for (int i = 0; i < n; i++) scanf("%d", v + i); if (n > 2) { for (int i = 0; i + 3 <= n; i++) { int a = v[i], b = v[i + 1], c = v[i + 2]; int ans1 = -1, ans2 = -1; set<int> ms; ms.insert(a); ms.insert(b); ms.insert(c); if (ms.size() == 1) continue; else if (ms.size() == 3) { if (a == *ms.begin()) ans1 = i, ans2 = i + 1; else if (a == *(++ms.begin())) ans1 = i, ans2 = i + 2; else if (a == *ms.rbegin()) ans1 = i, ans2 = i + 1; } else if (ms.size() == 2) { if (a == c) { int d = -1; if (i > 0) { d = v[i - 1]; if (d != a) ans1 = i - 1, ans2 = i; else ans1 = i, ans2 = i + 1; } else if (i + 3 < n) { d = v[i + 3]; if (d != a) ans1 = i + 2, ans2 = i + 3; else ans1 = i + 1, ans2 = i + 2; } else continue; } else if (a == b) ans1 = i + 1, ans2 = i + 2; else if (b == c) ans1 = i, ans2 = i + 1; } printf("%d %d\n", ans1 + 1, ans2 + 1); return 0; } } printf("-1\n"); return (0); }
#include <bits/stdc++.h> using namespace std; long long grid[2005][2005], cum[2005][2005]; int n; int main() { ios_base::sync_with_stdio(0); cin.tie(0); vector<int> vc, dec; set<int> st; int n; cin >> n; int tk; for (int i = 0; i < n; i++) { cin >> tk; st.insert(tk); vc.push_back(tk); } vector<int> tmp = vc; dec = vc; sort(tmp.begin(), tmp.end()); sort(dec.rbegin(), dec.rend()); if (st.size() == 1 || n <= 2) exit(puts("-1")); for (int i = 1; i < n; i++) { if (vc[i] != vc[i - 1]) { if (dec[i - 1] != vc[i] || vc[i - 1] != dec[i]) { if (tmp[i - 1] != vc[i] || vc[i - 1] != tmp[i]) { cout << i << " " << i + 1 << "\n"; return 0; } } if (tmp[i - 1] != vc[i] || vc[i - 1] != tmp[i]) { if (dec[i - 1] != vc[i] || vc[i - 1] != dec[i]) { cout << i << " " << i + 1 << "\n"; return 0; } } } } cout << "-1"; }
#include <bits/stdc++.h> using namespace std; pair<int, int> solve(vector<int> a) { vector<int> b = a; vector<int> c = a; sort(b.begin(), b.end()); sort(c.rbegin(), c.rend()); map<int, vector<int> > mp; for (int i = 0; i < (int)(a.size()); i++) mp[a[i]].push_back(i); map<int, vector<int> >::iterator itr, jtr; for (itr = mp.begin(); itr != mp.end(); itr++) { for (jtr = itr, ++jtr; jtr != mp.end(); jtr++) { vector<int> &x = itr->second; vector<int> &y = jtr->second; for (int i = 0; i < (int)(x.size()); i++) for (int j = 0; j < (int)(y.size()); j++) { swap(a[x[i]], a[y[j]]); if (a != b && a != c) return make_pair(x[i], y[j]); swap(a[x[i]], a[y[j]]); } } } return make_pair(-1, -1); } int main() { int n; cin >> n; vector<int> a(n); for (int i = 0; i < (int)(n); i++) cin >> a[i]; pair<int, int> ret = solve(a); if (ret.first == -1 && ret.second == -1) cout << -1 << endl; else cout << ret.first + 1 << " " << ret.second + 1 << endl; return 0; }
#include <bits/stdc++.h> using namespace std; int a[50], p[50], length[50], q[50], pos[50]; int main() { int n, m, top = 0; scanf("%d%d", &n, a); p[0] = 1; for (int i = 2; i <= n; i++) { scanf("%d", &m); if (m != a[top]) { a[++top] = m; p[top] = i; } else { length[top]++; } if (top >= 3) i = n + 1; } int num = 0; q[0] = a[0]; pos[0] = p[0]; for (int i = 1; i <= top; i++) { bool st = 1; for (int j = 0; j < i; j++) if (a[j] == a[i]) st = 0; if (st) { q[++num] = a[i]; pos[num] = p[i]; } } if (num == 0) printf("-1\n"); if (num == 1) { if (top <= 2) { int i = 0; while ((i <= top) && (length[i] == 0)) i++; if (i == 0) { printf("%d %d\n", p[1] - 1, p[1]); } else { if (i > top) { printf("-1\n"); } else { printf("%d %d\n", p[i] - 1, p[i]); } } } else { printf("%d %d\n", p[0], p[1]); } } if (num >= 2) { if (q[0] < q[1]) { if (q[1] < q[2]) printf("%d %d\n", pos[0], pos[1]); else printf("%d %d\n", pos[0], pos[2]); } else { if (q[1] > q[2]) printf("%d %d\n", pos[0], pos[1]); else printf("%d %d\n", pos[0], pos[2]); } } return 0; }
#include <bits/stdc++.h> using namespace std; long a[1000000], m, n, i, j, k, l, ma, mi; int main() { cin >> n; for (i = 1; i <= n; i++) cin >> a[i]; if (n <= 2) { cout << -1 << endl; return 0; } for (i = 1; i <= n - 2; i++) if (a[i] != a[i + 2]) { if (a[i] == a[i + 1]) { cout << i + 1 << " " << i + 2 << endl; return 0; } else if (a[i + 1] == a[i + 2]) { cout << i << " " << i + 1 << endl; return 0; } else { if (a[i] > a[i + 1] && a[i] > a[i + 2]) ma = i; else if (a[i + 1] > a[i] && a[i + 1] > a[i + 2]) ma = i + 1; else ma = i + 2; if (a[i] < a[i + 1] && a[i] < a[i + 2]) mi = i; else if (a[i + 1] < a[i] && a[i + 1] < a[i + 2]) mi = i + 1; else mi = i + 2; if (ma != i + 1) { if (ma != i + 2) cout << i << " " << i + 1 << endl; else cout << i + 2 << " " << i + 1 << endl; return 0; } if (mi != i + 1) { if (mi != i + 2) cout << i << " " << i + 1 << endl; else cout << i + 2 << " " << i + 1 << endl; return 0; } } } if (n == 3 && a[1] == a[3]) { cout << -1 << endl; return 0; } else if (a[1] != a[2]) cout << 1 << " " << 2 << endl; else cout << -1 << endl; }
#include <bits/stdc++.h> using namespace std; struct point { int v, p; bool friend operator<(const point& t1, const point& t2) { return t1.v < t2.v; } }; point a[1000000]; int main() { int n; cin >> n; int i; for (i = 0; i < n; i++) { cin >> a[i].v; a[i].p = i + 1; } sort(a, a + n); if (n > 2 && a[0].v != a[n - 2].v && !(a[0].p == n - 1 && a[n - 2].p == 1)) cout << a[0].p << " " << a[n - 2].p << endl; else if (n > 2 && a[1].v != a[n - 1].v && !(a[1].p == n && a[n - 1].p == 2)) cout << a[1].p << " " << a[n - 1].p << endl; else cout << -1 << endl; return 0; }
#include <bits/stdc++.h> using namespace std; int main() { int a[100001] = {}; int n; cin >> n; int isinc = 0; int isdec = 0; for (int i = 0; i < n; i++) cin >> a[i]; isinc = 1; isdec = 1; if (n <= 2) { cout << -1 << endl; return 0; } for (int i = 0; i < n - 1; i++) if (a[i + 1] < a[i]) isinc = 0; for (int i = 0; i < n - 1; i++) if (a[i + 1] > a[i]) isdec = 0; if (isinc == 1 && isdec == 1) { cout << -1 << endl; return 0; } for (int i = 1; i < n; i++) { if (a[0] != a[i]) { swap(a[0], a[i]); isinc = 1; isdec = 1; for (int j = 0; j < n - 1; j++) if (a[j + 1] < a[j]) isinc = 0; for (int j = 0; j < n - 1; j++) if (a[j + 1] > a[j]) isdec = 0; if (isinc == 1 || isdec == 1) { swap(a[0], a[i]); continue; } cout << 1 << ' ' << i + 1 << endl; return 0; } } for (int i = 0; i < n; i++) { if (i != 1) if (a[1] != a[i]) { swap(a[1], a[i]); isinc = 1; isdec = 1; for (int j = 0; j < n - 1; j++) if (a[j + 1] < a[j]) isinc = 0; for (int j = 0; j < n - 1; j++) if (a[j + 1] > a[j]) isdec = 0; if (isinc == 1 || isdec == 1) { swap(a[1], a[i]); continue; } cout << 2 << ' ' << i + 1 << endl; return 0; } } cout << -1 << endl; return 0; }
#include <bits/stdc++.h> int min(int x, int y) { return (x < y ? x : y); } int max(int x, int y) { return (x < y ? y : x); } unsigned int n, a[(100000 + 10)], maxl[(100000 + 10)], minl[(100000 + 10)]; void read() { scanf("%u", &n); unsigned int i; for (i = 1; i <= n; ++i) scanf("%u", &a[i]); } void solve() { unsigned int i, valmin = 1000000000, valmax = 0, imin = 0, imax = 0; for (i = 1; i <= n; ++i) { if (a[i] < valmin) { valmin = a[i]; minl[i] = i; } else minl[i] = minl[i - 1]; if (a[i] > valmax) { valmax = a[i]; maxl[i] = i; } else maxl[i] = maxl[i - 1]; } if (n <= 2 || valmin == valmax) { printf("-1\n"); return; } valmin = valmax = a[n]; ; imin = imax = n; for (i = n - 1; i >= 2; --i) { if (a[maxl[i - 1]] >= a[i] && a[i] >= valmin && a[maxl[i - 1]] > valmin) { if (a[maxl[i - 1]] > a[i]) printf("%u %u\n", maxl[i - 1], i); else printf("%u %u\n", i, imin); return; } else if (a[minl[i - 1]] <= a[i] && a[i] <= valmax && a[minl[i - 1]] < valmax) { if (a[minl[i - 1]] < a[i]) printf("%u %u\n", minl[i - 1], i); else printf("%u %u\n", i, imax); return; } else if (a[maxl[i - 1]] > a[i] && a[i] < valmax && a[maxl[i - 1]] != valmax) { printf("%d %d\n", maxl[i - 1], imax); return; } else if (a[minl[i - 1]] < a[i] && a[i] > valmin && a[minl[i - 1]] != valmin) { printf("%d %d\n", minl[i - 1], imin); return; } if (a[i] < valmin) { valmin = a[i]; imin = i; } else if (a[i] > valmax) { valmax = a[i]; imax = i; } } printf("-1\n"); } int main() { read(); solve(); return 0; }
#include <bits/stdc++.h> using namespace std; template <typename X> inline X abs(const X &a) { return a < 0 ? -a : a; } template <typename X> inline X sqr(const X &a) { return a * a; } template <class T> void _R(T &x) { cin >> x; } void _R(int &x) { scanf("%d", &x); } void _R(long long &x) { scanf("%i64d", &x); } void _R(double &x) { scanf("%lf", &x); } void _R(char &x) { scanf(" %c", &x); } void _R(char *x) { scanf("%s", x); } void R() {} template <class T, class... U> void R(T &head, U &...tail) { _R(head); R(tail...); } const int size = 1e5 + 2; const double eps = 0.0001; const long double PI = 3.1415926535897932384626433832795; const long long MOD = 1000000007; const long long INF = 1LL << 60; const long long MAX5 = 100001; const long long MAX6 = 1000001; void solution(); void include_file(); long long bin_search(long long left, long long right); int main() { ios_base::sync_with_stdio(false); solution(); return 0; } void include_file() { freopen("input.txt", "r", stdin); freopen("output.txt", "w", stdout); } inline bool isPrime(long long n) { for (int i = 2; i * i <= n; ++i) if (n % i == 0) return false; return true; } string ekv(string a) { if (a.size() & 1) return a; string x = ekv(a.substr(0, a.size() / 2)); string y = ekv(a.substr(a.size() / 2)); return min(x + y, y + x); } long long cubic_root(long long x) { long long l = 0, r = MAX6; while (l != r) { long long m = (l + r + 1) / 2; if (m * m * m > x) r = m - 1; else l = m; } return l; } float FastInvSqrt(float x) { float xhalf = 0.5f * x; int i = *(int *)&x; i = 0x5f3759df - (i >> 1); x = *(float *)&i; x = x * (1.5f - (xhalf * x * x)); return x; } long long gcd(long long a, long long b) { if (a == 0) return b; return gcd(b % a, a); } long long lcm(long long a, long long b) { return a / gcd(a, b) * b; } void yes() { cout << "YES"; } void no() { cout << "NO"; } void yes(bool res) { if (res) cout << "YES"; else cout << "NO"; } void dabl(double x) { printf("%.10lf", x); } namespace bits { template <typename X> inline X MAX(const X &a, const X &b) { return b & ((a - b) >> 31) | a & (~(a - b) >> 31); } template <typename X> inline X MIN(const X &a, const X &b) { return a & ((a - b) >> 31) | b & (~(a - b) >> 31); } bool check2(const long long n) { return n > 0 && (n & (n - 1)); } long long ostatok2(const long long n, const long long m) { return m & (n - 1); } template <typename X> void SWAP(X &a, X &b) { a ^= b; b ^= a; a ^= b; } size_t count_1_in_LL(unsigned long long n) { std::size_t i(0); for (; n; ++i) n &= n - 1; return i; } } // namespace bits vector<vector<int> > g; void solution() { int n; cin >> n; vector<int> a(n), b(n), c(n); for (long long i = 0; i < n; ++i) cin >> a[i]; ; b = c = a; sort((b).begin(), (b).end()); sort((c).begin(), (c).end(), greater<int>()); for (long long i = 1; i < n; ++i) { if (a[i] != a[i - 1]) { swap(a[i], a[i - 1]); if (a == b || a == c) { swap(a[i], a[i - 1]); } else { cout << i << " " << i + 1; return; } } } cout << -1; }
#include <bits/stdc++.h> using namespace std; double PI = 3.1415926535897932384626433832795; vector<int> v, v1, v2; int main() { int n; scanf("%d", &n); for (int i = 0; i < n; ++i) { int k; scanf("%d", &k); v.push_back(k); } v2 = v1 = v; sort(v1.begin(), v1.end()); sort(v2.rbegin(), v2.rend()); for (int i = 1; i < n; ++i) { if (v[i] != v[i - 1]) { swap(v[i], v[i - 1]); if (v == v1 || v == v2) { swap(v[i], v[i - 1]); continue; } printf("%d %d", i, i + 1); return 0; } } puts("-1"); return 0; }
#include <bits/stdc++.h> using namespace std; int main() { int n, x, y, z; vector<int> v; bool diff = false; cin >> n; v.resize(n); cin >> v[0]; for (int i = 1; i < n; i++) { cin >> v[i]; if (v[i] != v[i - 1]) diff = true; } if (n > 2 && diff) { for (int k = 0; k < 2; k++) { x = v[k]; y = v[k + 1]; for (int i = k + 2; i < n; i++) { z = v[i]; if (x != z) { if (y == z || (x < y && y < z) || (z < y && y < x)) cout << k + 1 << " " << k + 2 << endl; else if (x == y) cout << k + 2 << " " << i + 1 << endl; else cout << k + 1 << " " << i + 1 << endl; return 0; } } } } cout << -1 << endl; return 0; }
#include <bits/stdc++.h> using namespace std; int main() { long long int n, i, a; vector<long long int> v1, v2, v3; cin >> n; for (i = 0; i < n; i++) { cin >> a; v1.push_back(a); } v2 = v3 = v1; sort(v2.begin(), v2.end()); sort(v3.begin(), v3.end(), greater<long long int>()); for (long long int i = 1; i < n; i++) { if (v1[i] != v1[i - 1]) { swap(v1[i], v1[i - 1]); if (v1 == v2 || v1 == v3) { swap(v1[i], v1[i - 1]); continue; } cout << i << ' ' << i + 1; return 0; } } cout << "-1"; return 0; }
#include <bits/stdc++.h> using namespace std; long long a, arr[1000000]; bool ay7aga2() { for (int i = 0; i < a - 1; i++) { if (!(arr[i] <= arr[i + 1])) { return false; } } return true; } bool ay7aga() { for (int i = 0; i < a - 1; i++) { if (!(arr[i] >= arr[i + 1])) return ay7aga2(); } return true; } int main() { long long b = 0; cin >> a; for (int i = 0; i < a; i++) { cin >> arr[i]; if (i != 0 && arr[i - 1] == arr[i]) { b++; } } if (b == a - 1 || a <= 2) { cout << "-1" << endl; return 0; } for (int i = 0; i < a - 1; i++) { for (int j = i + 1; j < a; j++) { if (arr[i] != arr[j]) { swap(arr[i], arr[j]); if (ay7aga() == false) { cout << i + 1 << " " << j + 1 << endl; return 0; } else { swap(arr[i], arr[j]); } } } } cout << "-1" << endl; return 0; }
#include <bits/stdc++.h> using namespace std; bool cmp(int a, int b) { return a > b; } int main() { int n; int arr[100001]; cin >> n; bool f = 1; for (int i = 0; i < n; i++) { scanf("%d", &arr[i]); if (i && arr[i] != arr[0]) f = 0; } if (f || n == 1 || n == 2) cout << -1 << endl; else { f = 1; int c; if (arr[n - 2] != arr[n - 1]) { swap(arr[n - 2], arr[n - 1]); if (!is_sorted(arr, arr + n) && !is_sorted(arr, arr + n, cmp)) { cout << n << " " << n - 1 << endl; return 0; } swap(arr[n - 2], arr[n - 1]); } if (arr[n - 2] != arr[0]) { swap(arr[n - 2], arr[0]); if (!is_sorted(arr, arr + n) && !is_sorted(arr, arr + n, cmp)) { cout << 1 << " " << n - 1 << endl; return 0; } swap(arr[n - 2], arr[0]); } for (int i = 1; i < n - 2; i++) if (arr[i] != arr[n - 2]) { c = i, f = 0; break; } if (f) cout << -1 << endl; else cout << c + 1 << " " << n - 1 << endl; } }
#include <bits/stdc++.h> using namespace std; const int N = 100011; class T { public: int x, y; } a[N], b[N], c[N], d[N]; int n, m; bool cmp1(T a, T b) { if (a.x < b.x) return 1; return 0; } bool cmp2(T a, T b) { if (a.x > b.x) return 1; return 0; } bool unsorted() { int c1 = 0, c2 = 0; for (int i = (int)(1); i <= (int)(n - 1); i++) { if (a[i].x > a[i + 1].x) c1 = 1; if (a[i].x < a[i + 1].x) c2 = 1; } if (c1 == 1 && c2 == 1) return 1; return 0; } int main() { scanf("%d", &n); if (n <= 2) { puts("-1"); return 0; } for (int i = (int)(1); i <= (int)(n); i++) { scanf("%d", &a[i].x); a[i].y = i; b[i] = c[i] = a[i]; } sort(b + 1, b + 1 + n, cmp1); for (int i = (int)(1); i <= (int)(n); i++) if (a[i].x != b[i].x) { d[++m].x = i; d[m].y = b[i].y; } for (int i = (int)(2); i <= (int)(n); i++) if (a[i].x != a[1].x) { d[++m].x = 1; d[m].y = i; break; } int cnt = min(10, m); for (int k = (int)(1); k <= (int)(cnt); k++) { int i = d[k].x, j = d[k].y; swap(a[i], a[j]); if (unsorted()) { printf("%d %d\n", i, j); return 0; } swap(a[i], a[j]); } sort(c + 1, c + 1 + n, cmp2); m = 0; for (int i = (int)(1); i <= (int)(n); i++) if (a[i].x != c[i].x) { d[++m].x = i; d[m].y = c[i].y; } for (int i = (int)(2); i <= (int)(n); i++) if (a[i].x != a[1].x) { d[++m].x = 1; d[m].y = i; break; } cnt = min(10, m); for (int k = (int)(1); k <= (int)(cnt); k++) { int i = d[k].x, j = d[k].y; swap(a[i], a[j]); if (unsorted()) { printf("%d %d\n", i, j); return 0; } swap(a[i], a[j]); } puts("-1"); return 0; }
#include <bits/stdc++.h> using namespace std; const int INF = 1e9 + 5; const double E = 1e-6; const long long ll1 = 1; int n; vector<int> v; bool isSorted(vector<int> &v) { vector<int> tmp = v; sort(tmp.begin(), tmp.end()); bool b1 = (tmp == v); reverse(tmp.begin(), tmp.end()); bool b2 = (tmp == v); return (b1 || b2); } set<int> used; vector<int> id; void Solve3() { for (int i = 0; i < 3; ++i) { for (int j = i + 1; j < 3; ++j) { swap(v[id[i]], v[id[j]]); if (!isSorted(v)) { cout << id[i] + 1 << " " << id[j] + 1 << endl; exit(0); } swap(v[id[i]], v[id[j]]); } } assert(false); } void Solve2() { int e[2] = {v[id[0]], v[id[1]]}; vector<int> cid[2]; for (int i = 0; i < n; ++i) for (int t = 0; t < 2; ++t) if (e[t] == v[i]) cid[t].push_back(i); for (int t1 = 0; t1 < cid[0].size(); ++t1) { for (int t2 = 0; t2 < cid[1].size(); ++t2) { swap(v[cid[0][t1]], v[cid[1][t2]]); if (!isSorted(v)) { cout << cid[0][t1] + 1 << " " << cid[1][t2] + 1 << endl; exit(0); } swap(v[cid[0][t1]], v[cid[1][t2]]); } } cout << -1; exit(0); } int main() { cin >> n; v.resize(n); for (int i = 0; i < n; ++i) cin >> v[i]; for (int i = 0; i < n; ++i) { if (!used.count(v[i])) { id.push_back(i); used.insert(v[i]); } } if (used.size() >= 3) { Solve3(); } else if (used.size() == 2) { Solve2(); } else { cout << -1; } return 0; }
#include <bits/stdc++.h> using namespace std; long long v[100000 + 10]; int32_t main() { ios::sync_with_stdio(0); cin.tie(); bool flag = false, flag1 = 0, flag2 = 0, ffflag = 0; long long n, x, l = 0; cin >> n; cin >> v[0]; for (long long i = 1; i < n; i++) { cin >> v[i]; if (v[i] != v[i - 1]) flag = true; } if (n <= 2 || !flag) x = 1; else { for (long long i = 0; (i < n && !ffflag); i++) { for (long long j = i + 1; j < n; j++) { if (v[i] != v[j]) { flag1 = flag2 = 0; iter_swap(v + i, v + j); for (long long k = 1; k < n; k++) { if (v[k] > v[k - 1]) { flag1 = 1; break; } } for (long long k = 1; k < n; k++) { if (v[k] < v[k - 1]) { flag2 = 1; break; } } if (flag1 && flag2) { cout << i + 1 << " " << j + 1; ffflag = 1; break; } iter_swap(v + i, v + j); } } } } if (ffflag == 0) cout << -1; return 0; }
#include <bits/stdc++.h> using namespace std; const int md = 1e8; const long long int MAX = 1e5 + 5; int main() { long long int n; cin >> n; if (n <= 2) { cout << -1; return 0; } vector<long long int> vec(n), asc, dec; for (int i = 0; i < n; i++) cin >> vec[i]; asc = vec; dec = vec; sort(asc.begin(), asc.end()); sort(dec.rbegin(), dec.rend()); for (long long int i = n - 1; i >= 0; i--) { if (vec[i] == vec[n - 2]) continue; swap(vec[n - 2], vec[i]); if (vec != asc && vec != dec) { cout << n - 1 << " " << i + 1; return 0; } swap(vec[n - 2], vec[i]); } for (long long int i = 0; i < n; i++) { if (vec[i] == vec[1]) continue; swap(vec[1], vec[i]); if (vec != asc && vec != dec) { cout << "2 " << i + 1; return 0; } swap(vec[1], vec[i]); } cout << -1; return 0; }
#include <bits/stdc++.h> using namespace std; int i, j, n, k, res, idx; int A[100011]; map<int, int> M; int main() { cin >> n; int Max = 0; for (i = 0; i < n; i++) { cin >> A[i]; M[i]++; } if (n <= 2) { cout << -1 << endl; return 0; } else { for (i = 0; i < n - 1; i++) { if (A[i] != A[i + 1]) { swap(A[i], A[i + 1]); bool u = false, d = false; for (j = 0; j < n - 1; j++) if (A[j] > A[j + 1]) u = true; for (j = 0; j < n - 1; j++) if (A[j] < A[j + 1]) d = true; if (u && d) { cout << i + 1 << " " << i + 2 << endl; return 0; } swap(A[i], A[i + 1]); } } } cout << -1 << endl; return 0; }
#include <bits/stdc++.h> using namespace std; int n; int arr[100010]; bool sorted() { bool sort1 = true, sort2 = true; for (int i = 0; i < n - 1; i++) { if (arr[i] > arr[i + 1]) sort1 = false; if (arr[i] < arr[i + 1]) sort2 = false; } return sort1 | sort2; } int main() { cin >> n; if (n <= 2) { cout << -1 << endl; return 0; } bool flag = true; for (int i = 0; i < n; i++) { cin >> arr[i]; if (i > 0 && arr[i] != arr[i - 1]) flag = false; } if (flag) { cout << -1 << endl; return 0; } for (int i = 0; i < n; i++) { for (int j = i + 1; j < n; j++) { if (arr[i] == arr[j]) continue; swap(arr[i], arr[j]); if (!sorted()) { cout << i + 1 << " " << j + 1 << endl; return 0; } swap(arr[i], arr[j]); } } cout << -1 << endl; }
#include <bits/stdc++.h> using namespace std; inline bool Sorted(vector<int> &v) { bool gt = true, lt = true; for (int i = 1; i < v.size(); ++i) { if (v[i - 1] < v[i]) lt = false; if (v[i - 1] > v[i]) gt = false; } return gt || lt; } int main() { int n; cin >> n; vector<int> v(n); for (int i = 0; i < n; ++i) cin >> v[i]; set<int> ss(v.begin(), v.end()); if (n <= 2 || ss.size() == 1) { cout << -1 << endl; return 0; } if (ss.size() > 2) { vector<int> sv((ss).begin(), (ss).end()); int i = find((v).begin(), (v).end(), sv[0]) - v.begin(); int j = find((v).begin(), (v).end(), sv[1]) - v.begin(); int k = find((v).begin(), (v).end(), sv[2]) - v.begin(); swap(v[i], v[j]); if (!Sorted(v)) cout << i + 1 << " " << j + 1 << endl; else cout << j + 1 << " " << k + 1 << endl; } else { if (n == 3) { vector<int> vv(v); int sz = unique(vv.begin(), vv.end()) - vv.begin(); if (sz == 3) cout << -1 << endl; else { for (int i = 1; i < n; ++i) if (v[i - 1] != v[i]) cout << i << " " << i + 1 << endl; } } else { for (int i = 1; i < n; ++i) if (v[i - 1] != v[i]) { if (i + 1 == n || v[i] == v[i + 1]) cout << i << " " << i + 1 << endl; else if (i > 1) cout << i << " " << i + 1 << endl; else if (v[i + 2] == v[i]) cout << i << " " << i + 1 << endl; else cout << i + 1 << " " << i + 2; break; } } } return 0; }
#include <bits/stdc++.h> using namespace std; int main() { int n; scanf("%d", &n); ; vector<int> a(n), b, c; for (int i = 0; i < n; scanf("%d", &a[i++])) ; if (n < 3) { printf("%d\n", -1); ; return 0; } b = a; c = a; sort(b.begin(), b.end()); sort(c.rbegin(), c.rend()); bool ok = 0; int ri, rj; for (int i = 0; i + 1 < n && !ok; i++) { int j = i + 1; if (a[j] != a[i]) { swap(a[i], a[j]); if (a != b && a != c) { ok = 1; ri = i; rj = j; } swap(a[i], a[j]); } } if (!ok) { printf("%d\n", -1); ; } else printf("%d %d\n", ri + 1, rj + 1); return 0; }
#include <bits/stdc++.h> using namespace std; vector<int> a(100005); int main() { int n, i; scanf("%d", &n); a.resize(n); for (i = 0; i < n; i++) { scanf("%d", &a[i]); } if (n <= 2) { printf("-1\n"); return 0; } for (i = 1; i < n; i++) { if (a[i] != a[i - 1]) break; } if (i == n) { printf("-1\n"); return 0; } if (n == 3 && a[0] == a[2]) { printf("-1\n"); return 0; } vector<int> inc(a); sort(inc.begin(), inc.end()); vector<int> dec(inc); reverse(dec.begin(), dec.end()); for (i = 1; i < n; i++) { if (a[i] != a[i - 1]) { swap(a[i], a[i - 1]); if (a != inc && a != dec) { printf("%d %d\n", i, i + 1); return 0; } swap(a[i - 1], a[i]); } } printf("-1\n"); return 0; }
#include <bits/stdc++.h> using namespace std; int n, a[100005]; int test(int x, int y) { swap(a[x], a[y]); int da = 0, xi = 0; for (int i = 2; i <= n; i++) { if (a[i] > a[i - 1]) da = 1; else if (a[i] < a[i - 1]) xi = 1; } swap(a[x], a[y]); return da + xi; } int main() { cin >> n; for (int i = 1; i <= n; i++) cin >> a[i]; if (n <= 2) cout << -1 << endl; else { int p = 0; for (int i = 2; i < n; i++) if (a[i] != a[1] || a[i] != a[n]) { p = i; break; } if (p) { int i; for (i = 1; i <= n; i++) { if (a[p] != a[i] && test(i, p) == 2) { cout << i << " " << p << endl; break; } } if (i > n) cout << -1 << endl; } else cout << -1 << endl; } }
#include <bits/stdc++.h> using namespace std; using ull = unsigned long long; using ll = long long; using ld = long double; using D = double; using ii = pair<int, int>; using vi = vector<int>; using vii = vector<ii>; template <typename T> T sqr(T a) { return a * a; } template <typename T> T gcd(T a, T b) { return b ? gcd(b, a % b) : a; } template <typename T> T sgn(T a) { return a > 0 ? 1 : (a < 0 ? -1 : 0); } template <typename T> T abs(T a) { return a > 0 ? a : -a; } const int inf = 2e9; const ld st = 0.000001; const ld pi = acos((ld)-1); const ll MAXN = 1000000000 + 100; ll det(ll x, ll y, ll z, ll m) { return x * m - y * z; } int main() { ios::sync_with_stdio(0); cin.tie(NULL), cout.tie(NULL); int n; cin >> n; vector<int> a; set<int> s; for (int i = 0; i < n; i++) { int x; cin >> x; a.push_back(x); s.insert(x); } if (n == 3 && ((int)s.size()) == 2) { vector<int> t = a; vector<int> t1 = a; sort(t.begin(), t.end()); sort(t1.rbegin(), t1.rend()); if (t == a || t1 == a) { goto l1; } else { cout << -1; return 0; } } l1: if (((int)a.size()) == 2) { cout << -1; return 0; } if (((int)s.size()) == 1) { cout << -1; return 0; } if (n == 3) { int x = a[0]; for (int i = 1; i < n; i++) { if (x < a[i]) { cout << 1 << " " << i + 1; return 0; } } } if (((int)s.size()) > 2) { int x = a[1]; for (int i = 2; i < n; i++) { if (x != a[i]) { cout << 2 << " " << i + 1; return 0; } } } if (((int)s.size()) == 2) { vector<int> t = a; vector<int> t1 = a; sort(t1.rbegin(), t1.rend()); sort(t.begin(), t.end()); if (t == a || t1 == a) { int x = a[0]; for (int i = 1; i < n; i++) { if (a[i] != x) { cout << i << " " << i + 1; return 0; } } } else { int x = a[1]; for (int i = 2; i < n; i++) { if (a[i] != x) { cout << 2 << " " << i + 1; return 0; } } } } return 0; }
#include <bits/stdc++.h> using namespace std; const int INF = INT_MAX; const long long INFL = LLONG_MAX; const int output_precision = 15; const bool debug = true; int mn, mx, N, A[100100]; int main() { ios_base::sync_with_stdio(0); cout.precision(output_precision); cout << fixed; cout.tie(0); cin >> N; for (int(i) = 1, j1234 = N; (i) <= j1234; (i)++) cin >> A[i]; if (N <= 2) { cout << -1 << '\n'; return 0; } int identical = 1; for (int(i) = 1, j1234 = N; (i) <= j1234; (i)++) identical &= A[1] == A[i]; if (identical) { cout << -1 << '\n'; return 0; } for (int(i) = 1, j1234 = N; (i) <= j1234; (i)++) for (int(j) = 1, j1234 = N; (j) <= j1234; (j)++) if (i < j && A[i] != A[j]) { swap(A[i], A[j]); int sorted = 1; for (int(ii) = 1, j1234 = N - 1; (ii) <= j1234; (ii)++) sorted &= A[ii] <= A[ii + 1]; if (sorted) { swap(A[i], A[j]); continue; } sorted = 1; for (int(ii) = 1, j1234 = N - 1; (ii) <= j1234; (ii)++) sorted &= A[ii] >= A[ii + 1]; if (sorted) { swap(A[i], A[j]); continue; } cout << i << " " << j << '\n'; return 0; } cout << -1 << '\n'; return 0; }
#include <bits/stdc++.h> using namespace std; bool isSortedAc(std::vector<int> v) { for (int i = int(0); i < int(v.size() - 1); i++) { if (v[i + 1] > v[i]) return false; } return true; } bool isSortedDec(std::vector<int> v) { reverse(v.begin(), v.end()); return isSortedAc(v); } void run() { int n; cin >> n; std::vector<int> v; bool MyisSortedAc = true; bool MyisSortedDec = true; for (int i = int(0); i < int(n); i++) { int t; cin >> t; v.push_back(t); if (i != 0) { if (v[i] < v[i - 1]) MyisSortedAc = false; if (v[i] > v[i - 1]) MyisSortedDec = false; } } if (MyisSortedAc && MyisSortedDec) { cout << -1 << endl; return; } for (int i = int(0); i < int(v.size()); i++) { for (int j = int(i + 1); j < int(v.size()); j++) { if (v[i] != v[j]) { swap(v[i], v[j]); if (!isSortedAc(v) && !isSortedDec(v)) { i++; j++; cout << i << " " << j << endl; return; } swap(v[i], v[j]); } } } cout << -1 << endl; } int main(int argc, char const *argv[]) { run(); return 0; }
#include <bits/stdc++.h> using namespace std; int Number; int Arr[100000 + 5]; bool First, Second, Ok; int main() { scanf("%d", &Number); for (int i = 0; i < Number; i++) scanf("%d", &Arr[i]); for (int i = 0; i < Number - 1; i++) { if (Arr[i] == Arr[i + 1]) continue; First = Second = Ok = false; swap(Arr[i], Arr[i + 1]); for (int j = 0; j < Number - 1; j++) { if (Arr[j] < Arr[j + 1]) First = true; if (Arr[j] > Arr[j + 1]) Second = true; if (First && Second) break; } if (First && Second) { printf("%d %d", i + 1, i + 1 + 1); return 0; } swap(Arr[i], Arr[i + 1]); } puts("-1"); return 0; }
#include <bits/stdc++.h> using namespace std; const int maxn = 100005; int a[maxn], b[maxn], c[maxn]; int n; bool check() { int c1 = 0, c2 = 0; for (int i = 1; i <= n; i++) { if (a[i] != b[i]) c1 = 1; } for (int i = 1; i <= n; i++) { if (a[i] != c[i]) c2 = 1; } return (c1 & c2); } int fun() { for (int i = 1; i < n; i++) { if (a[i] != a[i + 1]) { swap(a[i], a[i + 1]); if (check()) { cout << i << " " << i + 1 << "\n"; return 1; } swap(a[i], a[i + 1]); } } return -1; } int main() { cin >> n; for (int i = 1; i <= n; i++) { cin >> a[i]; b[i] = c[i] = a[i]; } sort(b + 1, b + 1 + n); sort(c + 1, c + 1 + n, greater<int>()); if (fun() == -1) cout << "-1" << "\n"; return 0; }
#include <bits/stdc++.h> using namespace std; const int MAXN = 100020; int A[MAXN], N; bool is_sorted() { bool asc = true, desc = true; for (int i = 1; i < N; ++i) { if (A[i - 1] > A[i]) asc = false; if (A[i - 1] < A[i]) desc = false; } return asc || desc; } int main() { cin >> N; for (int i = 0; i < N; ++i) { cin >> A[i]; } if (N <= 2) { cout << -1 << endl; } else { if (is_sorted()) { for (int i = 1; i < N; ++i) { if (A[i - 1] != A[i]) { cout << i << " " << i + 1 << endl; return 0; } } } else { for (int i = 1; i < N; ++i) { if (A[i - 1] != A[i]) { swap(A[i - 1], A[i]); if (!is_sorted()) { cout << i << " " << i + 1 << endl; return 0; } swap(A[i - 1], A[i]); } } } cout << -1 << endl; } return 0; }
#include <bits/stdc++.h> using namespace std; vector<int> adj[100001]; bool visit[100001]; const int mod = 1000000007; int main() { ios_base::sync_with_stdio(false); cin.tie(NULL); cout.tie(NULL); int n, i, arr[100001], inc[100001], dec[100001]; cin >> n; for (long long i = 0; i < n; i += 1) { cin >> arr[i]; inc[i] = arr[i]; dec[i] = arr[i]; } sort(inc, inc + n); sort(dec, dec + n, greater<int>()); int f = 0; for (long long i = 0; i < n - 1; i += 1) if (arr[i] != arr[i + 1]) f = 1; if (n < 3 || !f) cout << -1; else { for (int k = 0; k < n; k++) { for (long long i = k + 1; i < n; i += 1) { int f = 0; if (arr[k] == arr[i]) continue; swap(arr[k], arr[i]); for (long long j = 0; j <= n - 1; j += 1) { if (arr[j] != inc[j]) { f = 1; break; } } if (f) { for (long long j = 0; j <= n - 1; j += 1) { if (arr[j] != dec[j]) { cout << k + 1 << " " << i + 1; return 0; } } } swap(arr[0], arr[i]); } } cout << -1; } return 0; }
#include <bits/stdc++.h> using namespace std; int main() { int n, a[100000], b[100000]; cin >> n; if (n < 3) { cout << -1 << endl; return 0; } for (int i = 0; i < n; i++) { cin >> a[i]; b[i] = a[i]; } sort(b, b + n); for (int i = 0; i < n; i++) { if (i + 1 < n && a[i] == a[i + 1]) continue; for (int j = i + 1; j < n; j++) { if (a[i] == a[j]) continue; swap(a[i], a[j]); bool bf = true, cf = true; for (int k = 0; k < n; k++) { if (a[k] != b[k]) bf = false; if (a[k] != b[n - 1 - k]) cf = false; } if (!bf && !cf) { cout << (i + 1) << " " << (j + 1) << endl; return 0; } swap(a[i], a[j]); } } cout << -1 << endl; }
#include <bits/stdc++.h> using namespace std; int n, a[100005], b[100005], c[100005]; bool cmp(int x, int y) { return x > y; } int main() { scanf("%d", &n); for (int i = 1; i <= n; ++i) scanf("%d", &a[i]); if (n <= 2) { puts("-1"); return 0; } for (int i = 1; i <= n; ++i) b[i] = c[i] = a[i]; sort(b + 1, b + 1 + n); sort(c + 1, c + 1 + n, cmp); for (int i = 1; i < n; ++i) { if (a[i] == a[i + 1]) continue; swap(a[i], a[i + 1]); int j = 1; while (j <= n && a[j] == b[j]) { j++; } if (j > n) { swap(a[i], a[i + 1]); continue; } j = 1; while (j <= n && a[j] == c[j]) { j++; } if (j <= n) { printf("%d %d\n", i, i + 1); return 0; } swap(a[i], a[i + 1]); } puts("-1"); return 0; }
#include <bits/stdc++.h> using namespace std; int cd[100005] = {0}; int dc[100005] = {0}; int n; int main() { int a; int i; int j; scanf("%d", &n); for (a = 1; a <= n; a++) { scanf("%d", &cd[a]); dc[a] = cd[a]; } if (n <= 2) { printf("-1\n"); return 0; } sort(dc + 1, dc + n + 1); for (i = 1; i < n; i++) { if (cd[i] == cd[i + 1]) continue; swap(cd[i], cd[i + 1]); j = 1; while (j <= n) { if (cd[j] != dc[j]) break; j++; } if (j == n + 1) { swap(cd[i], cd[i + 1]); continue; } j = 1; while (j <= n) { if (cd[j] != dc[n - j + 1]) break; j++; } if (j == n + 1) { swap(cd[i], cd[i + 1]); continue; } printf("%d %d\n", i, i + 1); return 0; } printf("-1\n"); }
#include <bits/stdc++.h> using namespace std; const int Max = 2e6 + 10; const int Mod = 1e9 + 7; const long long int Inf = 1LL << 62; long long int mxval[Max]; long long int mxpos[Max]; long long int ar[Max]; bool Sorted(int n) { long long int asc = 0, dsc = 0; for (int i = 1; i < n; i++) { if (ar[i] > ar[i + 1]) { dsc++; } if (ar[i] < ar[i + 1]) { asc++; } } return !asc or !dsc; } int main() { long long int n; cin >> n; for (int i = 1; i <= n; i++) { cin >> ar[i]; } if (n <= 2) { cout << -1 << endl; return 0; } for (int i = 1; i < n; i++) { if (ar[i] != ar[i + 1]) { swap(ar[i], ar[i + 1]); if (Sorted(n)) { swap(ar[i], ar[i + 1]); } else { cout << i << " " << i + 1 << endl; return 0; } } } cout << -1 << endl; return 0; }
#include <bits/stdc++.h> using namespace std; void swap(int *x, int *y) { int t; t = *x; *x = *y; *y = t; } bool isNonInc(int a[], int sz) { for (int i = 0; i < sz - 1; i++) if (a[i] < a[i + 1]) return 0; return 1; } bool isNonDec(int a[], int sz) { for (int i = 0; i < sz - 1; i++) if (a[i] > a[i + 1]) return 0; return 1; } int main() { int n, a[100010]; cin >> n; for (int i = 0; i < n; i++) cin >> a[i]; bool can = 0; int idx1, idx2, tmp, sz; int p[4]; for (int i = 0; i < n - 2; i++) { p[0] = a[i]; p[1] = a[i + 1]; p[2] = a[i + 2]; sz = 3; if (i < n - 3) { p[3] = a[i + 3]; sz = 4; } for (int idx1 = 0; idx1 < sz; idx1++) for (int idx2 = idx1 + 1; idx2 < sz; idx2++) { if (p[idx1] == p[idx2]) continue; swap(&p[idx1], &p[idx2]); if (isNonInc(p, sz) == 0 && isNonDec(p, sz) == 0) { can = 1; cout << i + idx1 + 1 << " " << i + idx2 + 1 << "\n"; goto X; } swap(&p[idx1], &p[idx2]); } } X: if (can == 0) cout << "-1\n"; return 0; }
#include <bits/stdc++.h> using namespace std; int a[100005], n; int main() { scanf("%d", &n); for (int i = 0; i <= n - 1; ++i) scanf("%d", &a[i]); bool ok = true; for (int i = 1; i <= n - 1; ++i) if (a[i - 1] != a[i]) { ok = false; break; } if (ok) { printf("-1"); return 0; } for (int i = 0; i <= n - 2; ++i) for (int j = i + 1; j <= n - 1; ++j) if (a[i] != a[j]) { swap(a[i], a[j]); bool ok; if (a[0] >= a[1]) { ok = true; for (int k = 2; k <= n - 1; ++k) if (a[k - 1] < a[k]) { ok = false; break; } if (ok) { swap(a[i], a[j]); continue; } } if (a[0] <= a[1]) { ok = true; for (int k = 2; k <= n - 1; ++k) if (a[k - 1] > a[k]) { ok = false; break; } if (ok) { swap(a[i], a[j]); continue; } } printf("%d %d\n", i + 1, j + 1); return 0; } printf("-1"); return 0; }
#include <bits/stdc++.h> using namespace std; int N; int main() { srand(time(0)); cin >> N; vector<int> v(N), in(N), dc(N); for (int i = 0; i < N; ++i) scanf(" %d", &v[i]); in = dc = v; sort(in.begin(), in.end()); sort(dc.begin(), dc.end()); reverse(dc.begin(), dc.end()); for (int i = 0; i < 1000; i++) { int L = rand() % N; int R = rand() % N; if (v[L] == v[R]) continue; swap(v[L], v[R]); if (v != in && v != dc) return cout << min(L, R) + 1 << " " << max(L, R) + 1 << endl, 0; swap(v[L], v[R]); } if (N > 2) for (int i = 1; i < N; i++) { int L = 0; int R = i; if (v[L] == v[R]) continue; swap(v[L], v[R]); if (v != in && v != dc) return cout << min(L, R) + 1 << " " << max(L, R) + 1 << endl, 0; swap(v[L], v[R]); } if (N > 2) for (int i = 2; i < N; i++) { int L = 1; int R = i; if (v[L] == v[R]) continue; swap(v[L], v[R]); if (v != in && v != dc) return cout << min(L, R) + 1 << " " << max(L, R) + 1 << endl, 0; swap(v[L], v[R]); } puts("-1"); return 0; }
#include <bits/stdc++.h> using namespace std; int a[1000000]; int sorted(int len) { int x; for (x = 0; x < len - 1; x++) if (a[x] > a[x + 1]) goto nexttest; return 1; nexttest: for (x = 0; x < len - 1; x++) if (a[x] < a[x + 1]) return 0; return 1; } int main() { int n, x; scanf("%d", &n); for (x = 0; x < n; x++) scanf("%d", a + x); for (x = 0; x < n - 1; x++) { if (a[x] != a[x + 1]) swap(a[x], a[x + 1]); else continue; if (sorted(n)) { swap(a[x], a[x + 1]); } else { printf("%d %d\n", x + 1, x + 2); return 0; } } printf("-1\n"); }
#include <bits/stdc++.h> using namespace std; int main() { int i, n, x = 0, y = 0, pos, pos1, temp; scanf("%d", &n); int a[n], b[n]; for (i = 0; i < n; i++) { scanf("%d", &a[i]); b[i] = a[i]; } if (n == 1 || n == 2) { printf("-1\n"); return 0; } sort(b, b + n); for (i = 0; i < n; i++) if (a[i] != b[i]) { x = 1; break; } for (i = n - 1; i >= 0; i--) if (a[i] != b[n - i - 1]) { y = 1; break; } if (x == 0 && y == 0) { printf("-1\n"); return 0; } x = 0; y = 0; for (i = 0; i < n; i++) { if (a[i] > a[i + 1]) { if (a[i + 1] >= a[i + 2]) { pos = i + 1; pos1 = i + 2; break; } else if (a[i + 1] < a[i + 2]) { if (a[i] != a[i + 2]) { pos = i + 1; pos1 = i + 3; break; } else { if (a[i + 1] >= a[i + 3]) { pos = i + 1; pos1 = i + 2; } else { pos = i + 2; pos1 = i + 3; } break; } } } else if (a[i] < a[i + 1]) { if (a[i + 1] <= a[i + 2]) { pos = i + 1; pos1 = i + 2; break; } else { if (a[i] != a[i + 2]) { pos = i + 1; pos1 = i + 3; break; } else { if (a[i + 1] <= a[i + 3]) { pos = i + 1; pos1 = i + 2; } else { pos = i + 2; pos1 = i + 3; } break; } } } else { if (a[i + 1] != a[i + 2]) { pos = i + 2; pos1 = i + 3; break; } } } temp = a[pos - 1]; a[pos - 1] = a[pos1 - 1]; a[pos1 - 1] = temp; for (i = 0; i < n; i++) if (a[i] != b[i]) { x = 1; break; } for (i = n - 1; i >= 0; i--) if (a[i] != b[n - i - 1]) { y = 1; break; } if (x == 0 || y == 0) { printf("-1\n"); return 0; } printf("%d %d\n", pos, pos1); return 0; }
#include <bits/stdc++.h> using namespace std; const int N = 1e5 + 5; int a[N]; int main() { int n; cin >> n; for (int i = 1; i <= n; i++) cin >> a[i]; if (n == 1 || n == 2) { return 0 * printf("-1\n"); } int cnt = 0; for (int i = 1; i <= n; i++) { if (a[i] == a[1]) cnt++; } if (cnt == n) { return 0 * printf("-1\n"); } if (n == 3 && a[1] == a[3]) { return 0 * printf("-1\n"); } int flag = 0; if (a[2] > a[1]) flag = 2; if (a[2] == a[1]) flag = 1; for (int i = 2; i <= n; i++) { if (flag == 1) { if (a[i + 1] == a[i]) continue; else { printf("%d %d\n", i + 1, i); break; } } else if (flag == 2) { if (a[i + 1] >= a[i]) { printf("%d %d\n", i, i - 1); break; } else { if (a[i - 1] == a[i + 1]) { int flag = 0; for (int j = i + 1; j < n; j++) { if (a[j] >= a[j + 1]) { continue; } else { flag = 1; break; } } if (flag) { printf("%d %d\n", i, i - 1); break; } else { flag = 0; swap(a[i], a[i + 1]); for (int j = i + 1; j < n; j++) { if (a[j] <= a[j + 1]) { continue; } else { flag = 1; break; } } if (flag) { printf("%d %d\n", i, i + 1); break; } else { swap(a[i], a[i + 1]); continue; } } } else { printf("%d %d\n", i - 1, i + 1); break; } } } else { if (a[i + 1] > a[i]) { if (a[i + 1] == a[i - 1]) { int flag = 0; for (int j = i + 1; j < n; j++) { if (a[j] <= a[j + 1]) { continue; } else { flag = 1; break; } } if (flag) { printf("%d %d\n", i, i - 1); break; } else { flag = 0; swap(a[i], a[i + 1]); for (int j = i + 1; j < n; j++) { if (a[j] >= a[j + 1]) { continue; } else { flag = 1; break; } } if (flag) { printf("%d %d\n", i, i + 1); break; } else { swap(a[i], a[i + 1]); continue; } } } else { printf("%d %d\n", i - 1, i + 1); break; } } else { printf("%d %d\n", i, i - 1); break; } } } }
#include <bits/stdc++.h> const unsigned long long inf = 1LL << 61; const double eps = 1e-5; using namespace std; int a[100000 + 5]; int main() { int n; cin >> n; for (int i = 1; i <= n; i++) scanf("%d", &a[i]); for (int i = 2; i <= n; i++) { if (a[i - 1] != a[i]) { swap(a[i - 1], a[i]); int mark1 = 1, mark2 = 1; for (int j = 2; j <= n; j++) { if (a[j - 1] > a[j]) mark1 = 0; if (a[j - 1] < a[j]) mark2 = 0; if (mark1 || mark2) continue; printf("%d %d\n", i - 1, i); return 0; } swap(a[i - 1], a[i]); } } puts("-1"); return 0; }
#include <bits/stdc++.h> using namespace std; struct flags_t { flags_t() : asc(true), desc(true), eq(true){}; bool asc; bool desc; bool eq; }; static struct flags_t checkarray(const vector<int>& v) { flags_t res; int prevelem = 0; for (int i = 0; i < (v.size()); ++i) { if (0 == i) { prevelem = v[i]; } else { res.asc = res.asc && (v[i] >= prevelem); res.desc = res.desc && (v[i] <= prevelem); res.eq = res.eq && (v[i] == prevelem); prevelem = v[i]; } } return res; } int main(int argc, char** argv) { int n; cin >> n; if (n < 3) { do { cout << -1 << endl; return 0; } while (0); } vector<int> v(n, 0); int prevelem; bool asc = true, desc = true, eq = true; for (int i = 0; i < (n); ++i) { cin >> v[i]; if (0 == i) { prevelem = v[i]; } else { asc = asc && (v[i] >= prevelem); desc = desc && (v[i] <= prevelem); eq = eq && (v[i] == prevelem); prevelem = v[i]; } } if (eq) { do { cout << -1 << endl; return 0; } while (0); } for (int i = 0; i < (n - 1); ++i) { for (int j = i + 1; j < n; j++) { if (v[i] != v[j]) { swap(v[i], v[j]); flags_t r = checkarray(v); if (!r.asc && !r.desc) { do { cout << i + 1 << ' ' << j + 1 << endl; return 0; } while (0); } swap(v[i], v[j]); } } } do { cout << -1 << endl; return 0; } while (0); }
#include <bits/stdc++.h> using namespace std; long long int n, x[100000 + 1]; bool sorted() { bool asc = 1, des = 1; for (int i = 1; i < n; ++i) { if (des && (x[i] < x[i - 1])) des = 0; if (asc && (x[i] > x[i - 1])) asc = 0; } return asc || des; } int main() { bool b = true; int i; scanf("%lld", &(n)); for (i = 0; i < n; ++i) { scanf("%lld", &(x[i])); } int num = x[0]; for (i = 1; i < n; ++i) { if (x[i] != num) { b = false; break; } } if (n > 2 && b == false) { for (; i < n; ++i) { swap(x[i], x[i - 1]); if (!sorted()) { printf("%d", (i)); printf(" "); printf("%d", (i + 1)); return 0; } swap(x[i], x[i - 1]); } } printf("%s", ("-1")); return 0; }
#include <bits/stdc++.h> using namespace std; int a[5], p[5], length[5], q[5], pos[5]; int main() { int n, top = 0; scanf("%d%d", &n, a); p[0] = 1; for (int i = 2; i <= n; i++) { int m; scanf("%d", &m); if ((top < 3) && (m != a[top])) { a[++top] = m; p[top] = i; } else { if (m == a[top]) length[top]++; } } int num = 0; q[0] = a[0]; pos[0] = p[0]; for (int i = 1; i <= top; i++) { bool st = 1; for (int j = 0; j < i; j++) if (a[j] == a[i]) st = 0; if (st) { q[++num] = a[i]; pos[num] = p[i]; } } if (num == 0) printf("-1\n"); if (num == 1) { if (top <= 2) { int i = 0; while ((!length[i]) && (i <= top)) i++; if (i == 0) { printf("%d %d\n", p[1] - 1, p[1]); } else { if (i > top) { printf("-1\n"); } else { printf("%d %d\n", p[i] - 1, p[i]); } } } else { printf("%d %d\n", p[0], p[1]); } } if (num >= 2) { if (q[0] < q[1]) { if (q[1] < q[2]) printf("%d %d\n", pos[0], pos[1]); else printf("%d %d\n", pos[0], pos[2]); } else { if (q[1] > q[2]) printf("%d %d\n", pos[0], pos[1]); else printf("%d %d\n", pos[0], pos[2]); } } return 0; }
#include <bits/stdc++.h> using namespace std; int a[100000]; int n; bool isSorted() { bool flag1 = true; for (int i = 0; i < n - 1; i++) if (a[i] > a[i + 1]) flag1 = false; bool flag2 = true; for (int i = 0; i < n - 1; i++) if (a[i] < a[i + 1]) flag2 = false; return flag1 || flag2; } int main() { cin >> n; for (int i = 0; i < n; i++) cin >> a[i]; bool flag = true; for (int i = 1; i < n; i++) if (a[0] != a[i]) flag = false; if (flag) { cout << -1; return 0; } for (int i = 0; i < n; i++) for (int j = 0; j < n; j++) { if (i == j || a[i] == a[j]) continue; swap(a[i], a[j]); if (!isSorted()) { cout << i + 1 << ' ' << j + 1; return 0; } swap(a[i], a[j]); } cout << -1; return 0; }
#include <bits/stdc++.h> using namespace std; const int MAXN = 100002; int main() { int vec[MAXN]; int sort1[MAXN]; int sort2[MAXN]; int n; scanf("%d", &n); for (int i = 0; i < n; ++i) { scanf("%d", &vec[i]); sort1[i] = sort2[i] = vec[i]; } if (n <= 2) { printf("-1\n"); return 0; } sort(sort1, sort1 + n); sort(sort2, sort2 + n, greater<int>()); for (int i = 1; i < n; ++i) if (!((vec[i] == sort1[i - 1] && vec[i - 1] == sort1[i]) || (vec[i] == sort2[i - 1] && vec[i - 1] == sort2[i]) || (vec[i] == vec[i - 1]))) { printf("%d %d", i, i + 1); return 0; } printf("-1\n"); return 0; }
#include <bits/stdc++.h> using std::vector; int main() { bool flag = false; bool spec = false; int n, t; vector<int> number; std::cin >> n; for (int i = 0; i < n; i++) { std::cin >> t; number.push_back(t); } for (int i = 1; i < number.size() - 1; i++) { if ((number[i] - number[i - 1] > 0 ? 1 : (number[i] - number[i - 1] < 0 ? -1 : 0)) == (number[i + 1] - number[i] > 0 ? 1 : (number[i + 1] - number[i] < 0 ? -1 : 0))) { if (number[i] != number[i - 1]) { flag = true; std::cout << i << " " << i + 1; break; } } else { if (number[i] == number[i + 1]) { flag = true; std::cout << i << " " << i + 1; break; } else if (number[i] == number[i - 1]) { flag = true; std::cout << i + 1 << " " << i + 2; break; } else if (number[i - 1] != number[i + 1]) { flag = true; std::cout << i << " " << i + 2; break; } else { if (spec) { if (number[i] != number[i + 1]) { flag = true; std::cout << i + 1 << " " << i + 2; break; } } spec = true; } } } if (!flag) std::cout << -1; return 0; }
#include <bits/stdc++.h> using namespace std; int a[100006]; void f(int &i) { i = 1000 * 1000; } bool all_elements_are_equal(int n) { for (int i = 0; i < n - 1; i++) { if (a[i] != a[i + 1]) return false; } return true; } bool array_is_sorted(int n) { for (int i = 0; i < n - 1; i++) { if (a[i] > a[i + 1]) return false; } return true; } bool array_is_sorted(int n, bool f) { for (int i = 0; i < n - 1; i++) { if (a[i] < a[i + 1]) return false; } return true; } bool sorted(int n) { return (array_is_sorted(n) || array_is_sorted(n, true)); } int main() { int n; cin >> n; if (n == 1 || n == 2) { cout << -1; return 0; } for (int i = 0; i < n; i++) { cin >> a[i]; } if (all_elements_are_equal(n)) { cout << -1; return 0; } for (int i = 0; i < n - 1; i++) { for (int j = i + 1; j < n; j++) { if (a[i] == a[j]) continue; { int t = a[i]; a[i] = a[j]; a[j] = t; }; if (!sorted(n)) { cout << i + 1 << " " << j + 1; return 0; } { int t = a[i]; a[i] = a[j]; a[j] = t; }; } } cout << -1; return 0; }
#include <bits/stdc++.h> using namespace std; const int nmax = 100111; int n; int m; int a[nmax]; int b[nmax]; int vt[nmax]; int tmp_value; int ans; bool check() { if (n <= 2) return false; bool not_same = false; for (int cs = 1; cs < n; cs++) if (a[cs] != a[cs - 1]) { not_same = true; break; } if (not_same == false) return false; return true; } bool check_solution() { bool check1 = true; for (int cs = 1; cs < n; cs++) if (!(a[cs] >= a[cs - 1])) { check1 = false; break; } if (check1) return false; bool check2 = true; for (int cs = 1; cs < n; cs++) if (!(a[cs] <= a[cs - 1])) { check2 = false; break; } if (check2) return false; return true; } int solve() { ans = -1; for (int cs = 1; cs < n; cs++) if (a[cs] != a[cs - 1]) { swap(a[cs], a[cs - 1]); if (check_solution()) { ans = cs; break; } swap(a[cs], a[cs - 1]); } if (ans == -1) cout << -1 << endl; else cout << ans << " " << ans + 1 << endl; return 0; } int main() { cin >> n; for (int cs = 0; cs < n; cs++) { scanf("%d", &tmp_value); a[cs] = tmp_value; } if (!check()) cout << -1 << endl; else solve(); return 0; }
#include <bits/stdc++.h> using namespace std; int A[100005], N; bool canBe() { bool aa = 1; bool bb = 1; for (int i = 0; i < (int)N - 1; i++) if (A[i] > A[i + 1]) aa = 0; for (int i = 0; i < (int)N - 1; i++) if (A[i] < A[i + 1]) bb = 0; if (aa == bb && aa == 0) return 1; return 0; } int main() { scanf("%d", &N); set<int> S; for (int i = 0; i < (int)N; i++) { scanf("%d", &A[i]); S.insert(A[i]); } if (S.size() == 1 || N <= 2) { puts("-1"); } else { bool found = 0; for (int j = 0; j < (int)4; j++) { for (int i = 0; i < (int)N; i++) if (i > j) { if (A[i] != A[j]) { swap(A[i], A[j]); if (canBe()) { printf("%d %d\n", j + 1, i + 1); return 0; } swap(A[i], A[j]); } } } puts("-1"); } return 0; }
#include <bits/stdc++.h> using namespace std; template <class T1> void deb(T1 e) { cout << e << endl; } template <class T1, class T2> void deb(T1 e1, T2 e2) { cout << e1 << " " << e2 << endl; } int arr[100005]; int main() { int N; while (cin >> N) { int same = 1; int pre; for (__typeof(0) i = (0); i < N; i++) { cin >> arr[i]; if (i == 0) { pre = arr[i]; continue; } same &= (pre == arr[i]); } if (N == 1 or N == 2 or same) { cout << -1 << endl; return 0; } else { for (__typeof(0) i = (0); i < N - 1; i++) { if (arr[i] != arr[i + 1]) { swap(arr[i], arr[i + 1]); int a = 1, d = 1; for (__typeof(0) j = (0); j < N - 1; j++) { a &= (arr[j] <= arr[j + 1]); d &= (arr[j] >= arr[j + 1]); } if (a or d) { swap(arr[i], arr[i + 1]); continue; } else { cout << i + 1 << " " << i + 1 + 1 << endl; return 0; } } } cout << -1 << endl; } } return 0; }
#include <bits/stdc++.h> using namespace std; int main() { ios::sync_with_stdio(0); cout.tie(0); cin.tie(0); cout.precision(10); bool vozr = 1, ub = 1, same; int n; cin >> n; vector<int> a(n); for (int i = 0; i < n; i++) { cin >> a[i]; if (i != 0 && a[i] > a[i - 1]) ub = 0; if (i != 0 && a[i] < a[i - 1]) vozr = 0; } if (n <= 2 || (vozr && ub)) { cout << -1 << '\n'; return 0; } if (vozr) { same = 1; for (int i = 2; i < n - 1; i++) { if (a[i] != a[i - 1]) same = 0; } if (same) { if (a[n - 2] == a[n - 1]) cout << 1 << ' ' << n - 1 << '\n'; else cout << n - 1 << ' ' << n << '\n'; } else cout << 1 << ' ' << n << '\n'; } else if (ub) { same = 1; for (int i = 2; i < n - 1; i++) { if (a[i] != a[i - 1]) same = 0; } if (same) { if (a[n - 2] == a[n - 1]) cout << 1 << ' ' << 2 << '\n'; else cout << n - 1 << ' ' << n << '\n'; } else cout << 1 << ' ' << n << '\n'; } else { if (n == 3) { if (a[0] == a[2]) cout << -1 << '\n'; else cout << 1 << ' ' << 3 << '\n'; } else { int minn = 1100000000, maxx = -1, id1, id2; for (int i = 0; i < n; i++) { if (a[i] < minn) { minn = a[i]; id1 = i; } if (a[i] >= maxx) { maxx = a[i]; id2 = i; } } if (id1 == 0) { if (id2 == n - 1) cout << 1 << ' ' << n << '\n'; else { if (id2 == 1) cout << 2 << ' ' << 3 << '\n'; else cout << 2 << ' ' << id2 + 1 << '\n'; } } else { if (id1 == 1) cout << 2 << ' ' << 3 << '\n'; else cout << 2 << ' ' << id1 + 1 << '\n'; } } } return 0; }
#include <bits/stdc++.h> using namespace std; int dp[100][100]; int main() { ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0); int n; cin >> n; if (n == 1 || n == 2) { cout << -1; return 0; } int m = INT_MAX; int mi = -1; int a[n]; int m2 = INT_MIN; int mi2 = -1; for (int i = 0; i < n; i++) { cin >> a[i]; if (m > a[i]) { m = a[i]; mi = i; } if (m == a[i] && i != 0 && i != n - 1) { mi = i; } if (m2 < a[i]) { m2 = a[i]; mi2 = i; } if (m2 == a[i] && i != 0 && i != n - 1) { mi2 = i; } } if (mi != mi2) { int t = a[mi2]; a[mi2] = a[mi]; a[mi] = t; int flag = 0; for (int i = 0; i < n - 1; i++) { if (a[i] >= a[i + 1]) { } else { flag = 1; } } if (flag) { int flag2 = 0; for (int i = 0; i < n - 1; i++) { if (a[i] <= a[i + 1]) { } else { flag2 = 1; } } if (flag2) { cout << mi + 1 << " " << mi2 + 1; return 0; } } } cout << -1; return 0; }
#include <bits/stdc++.h> using namespace std; int main() { int n; cin >> n; vector<int> arr(n), cre(n), decre(n); for (int i = 0; i < n; i++) { cin >> arr[i]; } cre = arr; sort(begin(cre), end(cre)); decre = cre; reverse(begin(decre), end(decre)); for (int i = 0; i < n - 1; i++) { if (arr[i] > arr[i + 1]) { swap(arr[i], arr[i + 1]); if (arr != cre) { cout << i + 1 << " " << i + 2; return 0; } swap(arr[i], arr[i + 1]); } } for (int i = 0; i < n - 1; i++) { if (arr[i] < arr[i + 1]) { swap(arr[i], arr[i + 1]); if (arr != decre) { cout << i + 1 << " " << i + 2; return 0; } swap(arr[i], arr[i + 1]); } } cout << -1; return 0; }
#include <bits/stdc++.h> const double PI = acos(-0); const int mod = 1000007; const int maxn = 1e5 + 10; const int inf = 0x3f3f3f3f; const int NEXT[][2] = {{-1, 0}, {1, 0}, {0, -1}, {0, 1}}; using namespace std; int n; vector<int> a, b, c; int main() { scanf("%d", &n); for (int i = 0; i < n; i++) { int x; scanf("%d", &x); a.push_back(x); } c = b = a; sort(b.begin(), b.end()); sort(c.rbegin(), c.rend()); bool flag = 1; for (int i = 1; i <= n - 1; i++) { if (a[i] != a[i - 1]) { swap(a[i], a[i - 1]); if (a != b and c != a) { printf("%d %d", i, i + 1); flag = 0; break; } swap(a[i], a[i - 1]); } } if (flag) printf("-1"); }
#include <bits/stdc++.h> using namespace std; int n, a[100005]; inline bool isX() { for (int i = 2; i <= n; i++) if (a[i - 1] > a[i]) return false; return true; } inline bool isN() { for (int i = 2; i <= n; i++) if (a[i - 1] < a[i]) return false; return true; } inline bool check() { return isX() || isN(); } inline bool One_Val() { for (int i = 2; i <= n; i++) if (a[i] != a[i - 1]) return false; return true; } int main() { scanf("%d", &n); for (int i = 1; i <= n; i++) scanf("%d", a + i); if (One_Val()) { printf("-1"); return 0; } for (int i = 1; i <= n; i++) for (int j = i + 1; j <= n; j++) if (a[i] != a[j]) { swap(a[i], a[j]); if (!check()) { printf("%d %d\n", i, j); return 0; } swap(a[i], a[j]); } printf("-1"); return 0; }
#include <bits/stdc++.h> using namespace std; vector<int> v; int n; bool is_from_small_to_high() { for (int i = 1; i < n; i++) { if (v[i] < v[i - 1]) { return false; } } return true; } bool is_from_high_to_small() { for (int i = 1; i < n; i++) { if (v[i] > v[i - 1]) { return false; } } return true; } int main() { scanf("%d", &n); v.clear(); set<int> s; for (int i = 0; i < n; i++) { int tmp; scanf("%d", &tmp); v.push_back(tmp); s.insert(tmp); } if (s.size() == 1) { printf("-1\n"); return 0; } if (n <= 100) { int f = -1; int s = -1; for (int i = 0; i < n; i++) { for (int j = i + 1; j < n; j++) { if (v[i] == v[j]) { continue; } swap(v[i], v[j]); if (!(is_from_high_to_small() || is_from_small_to_high())) { f = i + 1; s = j + 1; break; } swap(v[i], v[j]); } if (f != -1) { break; } } if (f == -1) { printf("-1\n"); } else { printf("%d %d\n", f, s); } return 0; } if (s.size() == 2) { vector<int> lol(2); int a = 0; for (set<int>::iterator it = s.begin(); it != s.end(); it++) { lol[a] = (*it); a++; } vector<int> pos1; vector<int> pos2; for (int i = 0; i < n; i++) { if (v[i] == lol[0]) { pos1.push_back(i); } if (v[i] == lol[1]) { pos2.push_back(i); } } for (int i = 0; i < pos1.size(); i++) { for (int j = 0; j < pos2.size(); j++) { int idx1 = pos1[i]; int idx2 = pos2[j]; swap(v[idx1], v[idx2]); if (!(is_from_high_to_small() || is_from_small_to_high())) { printf("%d %d\n", idx1 + 1, idx2 + 1); return 0; } swap(v[idx1], v[idx2]); } } printf("-1\n"); return 0; } vector<int> pos1; vector<int> pos2; vector<int> pos3; vector<int> lol(3); int a = 0; for (set<int>::iterator it = s.begin(); it != s.end(); it++) { lol[a] = (*it); a++; if (a == 3) { break; } } for (int i = 0; i < n; i++) { if (v[i] == lol[0]) { pos1.push_back(i); } if (v[i] == lol[1]) { pos2.push_back(i); } if (v[i] == lol[2]) { pos3.push_back(i); } } int idx1 = pos1[0]; int idx2 = pos2[0]; int idx3 = pos3[0]; swap(v[idx1], v[idx2]); if (!(is_from_high_to_small() || is_from_small_to_high())) { printf("%d %d\n", idx1 + 1, idx2 + 1); return 0; } printf("%d %d\n", idx1 + 1, idx3 + 1); return 0; }
#include <bits/stdc++.h> using namespace std; #pragma comment(linker, "/STACK:64000000") const int maxn = 1 << 17; const int inf = 1000000007; const int mod = 1000000007; int n, a[maxn]; vector<int> v; bool check() { bool res1 = true, res2 = true; for (int i = 0; i < n - 1; i++) res1 &= a[i] <= a[i + 1]; for (int i = 0; i < n - 1; i++) res2 &= a[i] >= a[i + 1]; return !(res1 || res2); } int main() { cin >> n; for (int i = 0; i < n; i++) cin >> a[i]; v.push_back(0); for (int i = 1; i < n; i++) if (a[i] != a[i - 1] || a[i] == a[i - 1] && (a[i] != a[i - 2] || i < 2)) v.push_back(i); for (int i = 0; i < v.size(); i++) for (int j = 0; j < v.size(); j++) if (a[v[i]] != a[v[j]]) { swap(a[v[i]], a[v[j]]); if (check()) { cout << v[i] + 1 << " " << v[j] + 1 << "\n"; return 0; } swap(a[v[i]], a[v[j]]); } cout << -1; return 0; }
#include <bits/stdc++.h> using namespace std; int sorted(int a[100001], int n) { int l = 0, i, s = 0; int b[100001] = {0}; for (i = 0; i < n; i++) b[i] = a[i]; sort(b, b + n); for (i = 0; i < n; i++) { if (a[i] != b[i]) { l = 0; break; } l++; } if (l != n) { s = 0; for (i = n - 1; i >= 0; i--) { if (a[s] != b[i]) { return 0; } s++; } } return 1; } int main() { int n, m, i, j, k, a, b, c[100001], l = 1; scanf("%d", &n); for (i = 0; i < n; i++) { scanf("%d", &c[i]); if (c[i] == b && i != 0) { l++; } else if (c[i] != b && i != 0) { l = 0; } b = c[i]; } if (l == n || n == 1 || n == 2) { printf("-1\n"); return 0; } int x; for (i = 0; i < n; i++) { for (j = i + 1; j < n; j++) { if (c[i] != c[j]) { swap(c[i], c[j]); x = sorted(c, n); if (x == 1) { swap(c[i], c[j]); continue; } printf("%d %d\n", i + 1, j + 1); return 0; } } } printf("-1\n"); return 0; }
#include <bits/stdc++.h> using namespace std; template <class T> T abs(T x) { return x > 0 ? x : -x; } int n; int m; int x[100000]; pair<int, int> y[100000]; int main() { scanf("%d", &n); for (int i = 0; i < n; i++) scanf("%d", &x[i]); m = 0; for (int i = 0; i < n; i++) { if (m >= 2 && x[i] == y[m - 1].first && x[i] == y[m - 2].first) continue; y[m++] = make_pair(x[i], i + 1); } n = m; int s1 = 0, s2 = 0; for (int i = 0; i + 1 < n; i++) { s1 += int(y[i].first > y[i + 1].first); s2 += int(y[i].first < y[i + 1].first); } for (int i = 0; i < n; i++) for (int j = 1; j <= 2 && i + j < n; j++) { if (y[i].first == y[i + j].first) continue; int t1 = s1, t2 = s2; for (int k = max(0, i - 1); k < min(n, i + j + 1); k++) { t1 -= int(y[k].first > y[k + 1].first); t2 -= int(y[k].first < y[k + 1].first); } swap(y[i], y[i + j]); for (int k = max(0, i - 1); k < min(n, i + j + 1); k++) { t1 += int(y[k].first > y[k + 1].first); t2 += int(y[k].first < y[k + 1].first); } swap(y[i], y[i + j]); if (t1 != 0 && t2 != 0) { printf("%d %d\n", y[i].second, y[i + j].second); return 0; } } printf("-1\n"); return 0; }
#include <bits/stdc++.h> using namespace std; int a[100010]; bool isok(int n) { int f1 = 0, f2 = 0; for (int i = 1; i < n; i++) { if (a[i - 1] < a[i]) f1 = 1; if (a[i - 1] > a[i]) f2 = 1; if (f1 && f2) return false; } return true; } int main() { set<int> S; int n; cin >> n; for (int i = 0; i < n; i++) { cin >> a[i]; S.insert(a[i]); } if (S.size() == 1 || n == 2) cout << "-1" << endl; else { for (int i = 1; i < n; i++) if (a[i] != a[i - 1]) { swap(a[i], a[i - 1]); if (!isok(n)) { cout << i << " " << i + 1 << endl; return 0; } swap(a[i], a[i - 1]); } cout << "-1" << endl; } }
#include <bits/stdc++.h> using namespace std; int n; int num[100010]; set<int> s; bool ok() { for (int i = 2; i < n; i++) { if (!((num[i] >= num[i - 1] && num[i] <= num[i + 1]) || (num[i] <= num[i - 1] && num[i] >= num[i + 1]))) { return true; } } return false; } int main() { while (scanf("%d", &n) != EOF) { s.clear(); for (int i = 1; i <= n; i++) { scanf("%d", &num[i]); s.insert(num[i]); } int size = s.size(); if (size == 1 || n <= 2) printf("-1\n"); else if (size >= 3) { int pos[3]; int cnt = 0; pos[0] = 1; for (int i = 2; i <= n; i++) { if (num[i] != num[pos[cnt]]) pos[++cnt] = i; if (cnt == 3) break; } int MAX = max(num[pos[0]], num[pos[1]]); MAX = max(MAX, num[pos[2]]); if (num[pos[0]] == MAX) printf("%d %d\n", pos[0], pos[1]); else if (num[pos[1]] == MAX) printf("%d %d\n", pos[0], pos[2]); else if (num[pos[2]] == MAX) printf("%d %d\n", pos[1], pos[2]); } else if (size == 2) { bool mark = false; for (int i = 2; i <= n; i++) { if (num[i] != num[i - 1]) { swap(num[i], num[i - 1]); if (ok()) { printf("%d %d\n", i, i - 1); mark = !mark; break; } swap(num[i], num[i - 1]); } } if (!mark) printf("-1\n"); } } return 0; }
#include <bits/stdc++.h> using namespace std; int main() { int n, s[100002]; scanf("%d", &n); for (int i = 0; i < n; i++) scanf("%d", &s[i]); if (n <= 2) { printf("-1\n"); return 0; } int p = -1; for (int i = 2; i < n; i++) { if (s[i] == s[0] && s[i] == s[1]) continue; else { p = i; if ((s[0] > s[1] && s[0] > s[p]) || (s[0] < s[1] && s[0] < s[p])) printf("1 2\n"); else if ((s[1] > s[0] && s[1] > s[p]) || (s[1] < s[0] && s[1] < s[p])) { if (s[0] != s[p]) { printf("1 %d\n", p + 1); } else if (n != 3) { printf("2 %d\n", p + 1); } else printf("-1\n"); } else printf("2 %d\n", p + 1); goto gg; } } printf("-1\n"); gg:; return 0; }