input stringlengths 20 127k | target stringlengths 20 119k | problem_id stringlengths 6 6 |
|---|---|---|
N, M = list(map(int, input().split()))
ab = [list(map(int, input().split())) for i in range(M)]
ans = 0
tyukan = []
saigo = []
for i in range(M):
if ab[i][0] == 1:
tyukan.append(ab[i][1])
for i in range(M):
if ab[i][0] in tyukan:
if ab[i][1] == N:
ans =1
break
print(('POSSIBLE' if ans == 1 else 'IMPOSSIBLE')) | N, M = list(map(int, input().split()))
matrix = [[] for i in range(N)]
for i in range(M):
a, b = list(map(int, input().split()))
matrix[a-1].append(b-1)
matrix[b-1].append(a-1)
for i in matrix[0]:
if N-1 in matrix[i]:
print('POSSIBLE')
break
else:
print('IMPOSSIBLE') | p03645 |
N, M = list(map(int, input().split()))
matrix = [[] for i in range(N)]
check1 = [0] * N
check1[0] = 1
for i in range(M):
a, b = list(map(int, input().split()))
a, b = a-1, b-1
matrix[a].append(b)
matrix[b].append(a)
for i in matrix[0]:
if (N-1) in matrix[i]:
print('POSSIBLE')
break
else:
print('IMPOSSIBLE') | N, M = list(map(int, input().split()))
check = [0] * N
check[0] = 1
ab = []
for i in range(M):
a, b = list(map(int, input().split()))
ab.append([a, b])
if a == 1:
check[b-1] = 1
for a, b in ab:
if check[a-1] == 1 and b == N:
print('POSSIBLE')
break
else:
print('IMPOSSIBLE')
| p03645 |
import itertools
n, m = [int(_) for _ in input().split()]
a = []
b = []
for i in range(0, m):
ai, bi = [int(_) for _ in input().split()]
a.append(ai)
b.append(bi)
flag = False
for i, j in itertools.product(list(range(0, m)), list(range(0, m))):
if a[i] == 1 and b[i] == a[j] and b[j] == n:
flag = True
if flag:
print('POSSIBLE')
else:
print('IMPOSSIBLE') | import itertools
n, m = [int(_) for _ in input().split()]
a = []
b = []
for i in range(0, m):
ai, bi = [int(_) for _ in input().split()]
a.append(ai)
b.append(bi)
first = [b[i] for i in range(0, m) if a[i] == 1]
second = [a[i] for i in range(0, m) if b[i] == n]
if set(first) & set(second):
print('POSSIBLE')
else:
print('IMPOSSIBLE') | p03645 |
N,M = list(map(int,input().split()))
ab = [list(map(int,input().split())) for i in range(M)]
flag = 0
for i in range(M):
if ab[i][0] == 1:
j = 0
for j in range(M):
if ab[j] == [ab[i][1],N]:
print("POSSIBLE")
flag = 1
break
if flag == 1:
break
if flag == 0:
print("IMPOSSIBLE") | N,M = list(map(int,input().split()))
voy = [[] for i in range(N)]
for i in range(M):
a,b = list(map(int,input().split()))
voy[a-1].append(b)
alen = len(voy[0])
flag = 0
for j in range(alen):
qu = voy[0][j]-1
if N in voy[qu]:
print("POSSIBLE")
flag = 1
break
if flag == 0:
print("IMPOSSIBLE") | p03645 |
import sys
N,M = list(map(int,sys.stdin.readline().split()))
ab = []
start = []
goal = []
for i in range(M):
ab.append(list(map(int,sys.stdin.readline().split())))
for i in ab:
if i[0] == 1:
start.append(i[1])
if i[1] == N:
goal.append(i[0])
ans = 'IMPOSSIBLE'
for i in range(1,N+1):
if i in start and i in goal:
ans = 'POSSIBLE'
break
print(ans) | import sys
N,M = list(map(int,sys.stdin.readline().split()))
start = []
goal = []
for i in range(M):
a,b = list(map(int,sys.stdin.readline().split()))
if a == 1:
start.append(b)
if b == N:
goal.append(a)
ans = 'IMPOSSIBLE'
seta = set(start)
setg = set(goal)
for i in seta:
if i in setg:
ans = 'POSSIBLE'
break
print(ans) | p03645 |
n, m = list(map(int, input().split()))
l = [tuple(map(int, input().split())) for i in range(m)]
c = [[] for _ in range(n+1)]
for x in l:
c[x[0]].append(x[1])
c[x[1]].append(x[0])
if set(c[1])&set(c[n]):
print("POSSIBLE")
else:
print("IMPOSSIBLE") | import sys
readline = sys.stdin.buffer.readline
ni = lambda: int(readline().rstrip())
nm = lambda: list(map(int, readline().split()))
nl = lambda: list(map(int, readline().split()))
def solve():
n, m = nm()
G = [list() for _ in range(n)]
for _ in range(m):
u, v = nm()
u -= 1; v -= 1
G[u].append(v)
G[v].append(u)
if (set(G[0]) & set(G[n-1])):
print('POSSIBLE')
else:
print('IMPOSSIBLE')
return
solve()
# T = ni()
# for _ in range(T):
# solve()
| p03645 |
n,m=list(map(int,input().split()))
one_to=set()
to_n=set()
for i in range(m):
a,b=list(map(int,input().split()))
if a==1:
one_to.add(b)
elif b==n:
to_n.add(a)
one_to=list(one_to)
flag=False
for i in range(len(one_to)):
if one_to[i] in to_n:
flag=True
break
print(("POSSIBLE" if flag else "IMPOSSIBLE")) | n,m=list(map(int,input().split()))
one_to=[0]*(n+1)
to_n=[0]*(n+1)
for i in range(m):
a,b=list(map(int,input().split()))
if a==1:
one_to[b]=1
elif b==n:
to_n[a]=1
flag=False
for i in range(2,n):
if one_to[i]==1 and to_n[i]==1:
flag=True
break
print(("POSSIBLE" if flag else "IMPOSSIBLE")) | p03645 |
n,m = list(map(int,input().split()))
graph = [[0 for i in range(n)] for j in range(n)]
for i in range(m):
a,b = list(map(int,input().split()))
graph[a-1][b-1] = 1
graph[b-1][a-1] = 1
flag = False
for i in range(n):
if graph[0][i] == 1:
if graph[i][n-1] == 1:
flag = True
break
if flag:
print("POSSIBLE")
else:
print("IMPOSSIBLE")
| n,m = list(map(int,input().split()))
iki = []
iki2 = []
for i in range(m):
a,b = list(map(int,input().split()))
if a == 1:
iki.append(b)
if b == n:
iki2.append(a)
flag = False
for i in iki:
if i in iki2:
flag = True
break
if flag:
print("POSSIBLE")
else:
print("IMPOSSIBLE")
| p03645 |
N,M = list(map(int,input().split()))
edge = []
p = 'POSSIBLE'
i = 'IMPOSSIBLE'
for _ in range(M):
edge.append(tuple(map(int,input().split())))
from1 = []
is_reach = False
for go,to in sorted(edge,key=lambda x:x[0]):
if go == 1:
from1.append(to)
else:
if go in from1 and to == N:
is_reach = True
break
print((p if is_reach else i)) | N,M = list(map(int,input().split()))
edge = []
p = 'POSSIBLE'
i = 'IMPOSSIBLE'
for _ in range(M):
edge.append(list(map(int,input().split())))
from1 = set()
is_reach = False
for go,to in sorted(edge,key=lambda x:x[0]):
if go == 1:
from1.add(to)
else:
if go in from1 and to == N:
is_reach = True
break
print((p if is_reach else i)) | p03645 |
N,M = list(map(int,input().split()))
ab= [list(map(int,input().split())) for i in range(M)]
n = len(ab)
for i in range(n):
if ab[i][1] != N:
continue
for j in range(n):
if ab[i][0] == ab[j][1] and ab[j][0] == 1:
print('POSSIBLE')
exit()
print('IMPOSSIBLE') | N,M = list(map(int,input().split()))
s = []
g = []
for i in range(M):
a,b = list(map(int,input().split()))
if a == 1:
s.append(b)
elif b == N:
g.append(a)
ans = set(s) & set(g)
if len(ans) >= 1:
print('POSSIBLE')
else:
print('IMPOSSIBLE')
| p03645 |
N,M = list(map(int, input().split()))
A,B = [],[]
AtN,Bf1 = [],[]
for i in range(M):
a,b = list(map(int, input().split()))
if a == 1:
Bf1 += [b]
elif b == N:
AtN += [a]
if (any((b in AtN) for b in Bf1)):
print("POSSIBLE")
else:
print("IMPOSSIBLE") | N,M = list(map(int, input().split()))
AtN,Bf1 = set(),set()
for i in range(M):
a,b = list(map(int, input().split()))
if a == 1:
Bf1.add(b)
elif b == N:
AtN.add(a)
if (any((b in AtN) for b in Bf1)):
print("POSSIBLE")
else:
print("IMPOSSIBLE") | p03645 |
N,M=list(map(int,input().split()))
nekotyann=[]
wanntyann=[]
ans="IMPOSSIBLE"
for i in range(M):
a,b=list(map(int,input().split()))
if a==1:
nekotyann.append(b)
if b==N:
wanntyann.append(a)
for i in range(len(wanntyann)):
if wanntyann[i] in nekotyann:
ans="POSSIBLE"
break
print(ans)
| N,M=list(map(int,input().split()))
nekotyann=[0]*N
wanntyann=[0]*N
ans="IMPOSSIBLE"
for i in range(M):
a,b=list(map(int,input().split()))
if a==1:
nekotyann[b-1]+=1
if b==N:
wanntyann[a-1]+=1
for k in range(N):
if nekotyann[k]!=0 and wanntyann[k]!=0:
ans="POSSIBLE"
break
print(ans)
| p03645 |
N, M = list(map(int, input().split()))
s = [[] for i in range(N+1)]
e = [[] for i in range(N+1)]
for i in range(M):
a, b = list(map(int, input().split()))
s[a].append(b)
e[b].append(a)
for i in s[1]:
for j in e[N]:
if i == j:
print('POSSIBLE')
exit()
print('IMPOSSIBLE') | N, M = list(map(int, input().split()))
s = [[] for i in range(N+1)]
e = [[] for i in range(N+1)]
for i in range(M):
a, b = list(map(int, input().split()))
s[a].append(b)
e[b].append(a)
for i in s[1]:
if N in s[i]:
print('POSSIBLE')
exit()
print('IMPOSSIBLE') | p03645 |
n, m = (int(i) for i in input().split())
a,b = [0 for i in range(m)],[0 for i in range(m)]
g = [[0 for i in range(m)] for j in range(m)]
OK = False
for i in range(m):
a[i],b[i] = list(map(int, input().split()))
a[i]-=1
b[i]-=1
for i in range(m):
if a[i]==0:
v = b[i]
for j in range(m):
if a[j]==v and b[j]==n-1:
OK = True
print(('POSSIBLE' if OK else 'IMPOSSIBLE'))
| n, m = (int(i) for i in input().split())
a,b = [0 for i in range(m)],[0 for i in range(m)]
g = [[] for i in range(n)]
OK = False
for i in range(m):
a[i],b[i] = list(map(int, input().split()))
a[i]-=1
b[i]-=1
g[a[i]].append(b[i])
g[b[i]].append(a[i])
for i in range(m):
if a[i]==0 and n-1 in g[b[i]]:
OK = True
print(('POSSIBLE' if OK else 'IMPOSSIBLE'))
| p03645 |
N, M = list(map(int, input().split()))
a = [0 for i in range(M)]
b = [0 for i in range(M)]
c = []
for i in range(M):
a[i], b[i] = list(map(int, input().split()))
if a[i] == 1:
c.append(b[i])
flag = 0
for k in c:
if k == N:
flag = 1
break
else:
for i in range(M):
if a[i] == k and b[i] == N:
flag = 1
break
if flag == 1:
break
if flag == 0:
print("IMPOSSIBLE")
else:
print("POSSIBLE")
| N, M = list(map(int, input().split()))
a = [0 for i in range(M)]
b = [0 for i in range(M)]
c = []
d = []
flag = 0
for i in range(M):
a[i], b[i] = list(map(int, input().split()))
if a[i] == 1:
c.append(b[i])
if b[i] == N:
flag = 1
if b[i] == N:
d.append(a[i])
if a[i] == 1:
flag = 1
e = set(c) | set(d)
if len(c) + len(d) == len(e):
flag = 0
else:
flag = 1
if flag == 0:
print("IMPOSSIBLE")
else:
print("POSSIBLE")
| p03645 |
def inpl(): return input().split()
def get_str(bl): return 'POSSIBLE' if bl else 'IMPOSSIBLE'
n, m = list(map(int, inpl()))
M = list(tuple(map(int, inpl())) for _ in range(m))#[(a, b), ..., (a, b)]
X = list(tuple((a, b)) for a, b in M if a == 1)
Y = list(tuple((a, b)) for a, b in M if b == n)
XB = set(list(b for _, b in X))
YA = set(list(a for a, _ in Y))
print((get_str(len(XB & YA) > 0))) | def main():
import sys
input = sys.stdin.readline
N, M = list(map(int, input().split()))
g = tuple(set() for _ in range(N))
for _ in range(M):
a, b = (int(x) - 1 for x in input().split())
g[a].add(b)
g[b].add(a)
intersect = {u_1 for u_1 in g[0]} & {u_N for u_N in g[N - 1]}
print(('POSSIBLE' if intersect else 'IMPOSSIBLE'))
if __name__ == '__main__':
main()
| p03645 |
# coding: utf-8
# Here your code !
a = list(map((int), input().split(' ')))
N, M = a[0], a[1]
first = []
second = []
for i in range(M):
b = list(map((int),input().split(' ')))
start, end = b[0], b[1]
if start == 1:
first.append(end)
if end == N:
second.append(start)
first_set = set(first)
second_set = set(second)
matched_l = list(first_set & second_set)
if matched_l is None or len(matched_l) == 0:
print('IMPOSSIBLE')
else:
print('POSSIBLE')
| import sys
input = sys.stdin.readline
a = list(map((int), input().split(' ')))
N, M = a[0], a[1]
first = []
second = []
for i in range(M):
b = list(map((int),input().split(' ')))
start, end = b[0], b[1]
if start == 1:
first.append(end)
if end == N:
second.append(start)
first_set = set(first)
second_set = set(second)
matched_l = list(first_set & second_set)
if matched_l is None or len(matched_l) == 0:
print('IMPOSSIBLE')
else:
print('POSSIBLE') | p03645 |
N,M=list(map(int,input().split()))
A=[list(map(int,input().split())) for i in range(M)]
D=[[]for i in range(N)]
for i in range(M):
D[A[i][0]-1].append(A[i][1]-1)
D[A[i][1]-1].append(A[i][0]-1)
for i in D[-1]:
for j in D[0]:
if i==j:
print('POSSIBLE')
exit()
print('IMPOSSIBLE') | N,M=list(map(int,input().split()))
A=[list(map(int,input().split())) for i in range(M)]
D=[[]for i in range(N)]
for i in range(M):
D[A[i][0]-1].append(A[i][1]-1)
D[A[i][1]-1].append(A[i][0]-1)
a=len(D[-1])
b=len(D[0])
c=len(set(D[-1]+D[0]))
if a+b==c:
print('IMPOSSIBLE')
else:
print('POSSIBLE') | p03645 |
N, M = list(map(int, input().split()))
start = []
goal = []
for i in range(M):
a, b = list(map(int, input().split()))
if a == 1:
start.append(b)
if b == N:
goal.append(a)
for i in range(len(start)):
if start[i] in goal:
print("POSSIBLE")
exit()
print("IMPOSSIBLE") | N, M = list(map(int, input().split()))
start = set()
goal = set()
for i in range(M):
a, b = list(map(int, input().split()))
if a == 1:
start.add(b)
if b == N:
goal.add(a)
if len(start & goal) != 0:
print("POSSIBLE")
else:
print("IMPOSSIBLE") | p03645 |
n,m=list(map(int,input().split()))
a1=[]
an=[]
for i in range(m):
ai,bi=list(map(int,input().split()))
if ai==1:
a1.append(bi)
elif bi==n:
an.append(ai)
a1.sort()
an.sort()
flag = False
for i in range(len(a1)):
if a1[i] in an:
flag = True
break
if flag==True:
print("POSSIBLE")
else:
print("IMPOSSIBLE") |
n,m=list(map(int,input().split()))
a1=set()
an=set()
for i in range(m):
ai,bi=list(map(int,input().split()))
if ai==1:
a1.add(bi)
elif bi==n:
an.add(ai)
if len(a1&an)==0:
print("IMPOSSIBLE")
else:
print("POSSIBLE")
| p03645 |
n,m=list(map(int,input().split()))
r=[[] for i in range(n+1)]
#r=[]*(n+1)
for i in range(m):
ai,bi=list(map(int,input().split()))
if not bi in r[ai]:
r[ai].append(bi)
r[bi].append(ai)
yn=""
for i in range(2,n):
if (i in r[1]) and (i in r[n]):
print("POSSIBLE")
yn="POSSIBLE"
break
if yn=="":
print("IMPOSSIBLE") | n,m=list(map(int,input().split()))
#r=[[] for i in range(n+1)]
r=[set() for i in range(n+1)]
for i in range(m):
ai,bi=list(map(int,input().split()))
if not bi in r[ai]:
# r[ai].append(bi)
# r[bi].append(ai)
r[ai].add(bi)
r[bi].add(ai)
yn=""
for i in range(2,n):
if (i in r[1]) and (i in r[n]):
print("POSSIBLE")
yn="POSSIBLE"
break
if yn=="":
print("IMPOSSIBLE") | p03645 |
n,m=list(map(int,input().split()))
a=[[int(i) for i in input().split()]for i in range(m)]
s=set()
for i in a:
if i[1]==n:
s.add(i[0])
for i in a:
if i[0]==1 and i[1] in s:
print('POSSIBLE')
exit()
print('IMPOSSIBLE') | n,m=list(map(int,input().split()))
a=[[int(i) for i in input().split()]for i in range(m)]
b=[False]*n
for i in a:
if i[1]==n:
b[i[0]-1]=True
for i in a:
if i[0]==1 and b[i[1]-1]==True :
print('POSSIBLE')
exit()
print('IMPOSSIBLE') | p03645 |
N,M=[int(i) for i in input().split()]
a=[]
b=[]
c=[]
flag=False
for i in range(M):
x,y=list(map(int,input().split()))
a.append(x)
b.append(y)
if x==1:
c.append(y)
for i in range(M):
if b[i]==N:
flag=a[i] in c
if flag==False:
print("IMPOSSIBLE")
else:
print("POSSIBLE")
| N,M=[int(i) for i in input().split()]
a=[]
b=[]
c=[]
for i in range(M):
x,y=[int(i) for i in input().split()]
if x==1 :
c.append(y)
if y==N:
c.append(x)
if len(c)==len(set(c)):
print("IMPOSSIBLE")
else:
print("POSSIBLE")
| p03645 |
#真に大切なのは中間点となる要素
N, M = list(map(int, input().split()))
an = set()
nb = set()
for i in range(M):
a, b = list(map(int, input().split()))
if a == 1:
an.add(b)
elif b == N:
nb.add(a)
print(('IMPOSSIBLE' if len(an&nb)==0 else 'POSSIBLE')) | #真に大切なのは中間点となる要素
N, M = list(map(int, input().split()))
an = []
nb = []
for i in range(M):
a, b = list(map(int, input().split()))
if a == 1:
an.append(b)
elif b == N:
nb.append(a)
print(('IMPOSSIBLE' if len(set(an)&set(nb))==0 else 'POSSIBLE')) | p03645 |
n,m=list(map(int,input().split()))
data=[]
for i in range(m):
a,b=list(map(int,input().split()))
if a==1:
if b not in data:
data.append(b)
else:
print('POSSIBLE')
exit()
elif b==n:
if a not in data:
data.append(a)
else:
print('POSSIBLE')
exit()
print('IMPOSSIBLE') | n,m=list(map(int,input().split()))
data=[0]*n
for i in range(m):
a,b=list(map(int,input().split()))
if a==1:
data[b-1]+=1
if data[b-1]==2:
print('POSSIBLE')
exit()
if b==n:
data[a-1]+=1
if data[a-1]==2:
print('POSSIBLE')
exit()
print('IMPOSSIBLE') | p03645 |
# -*- coding: utf-8 -*-
N, M = list(map(int, input().split()))
abM = [list(map(int, input().split())) for i in range(M)]
transit = []
transit2 = []
for i in range(M):
if abM[i][0] == 1:
transit.append(abM[i][1])
if abM[i][1] == N:
transit2.append(abM[i][0])
# setで共通要素の集合を取ってみる
if len(set(transit) & set(transit2)) != 0:
print("POSSIBLE")
else:
print("IMPOSSIBLE") | # -*- coding: utf-8 -*-
N, M = list(map(int, input().split()))
# 1からある島への便があるかを保持
transit = [False] * N
# ある島からNへの便があるかを保持
transit2 = [False] * N
for i in range(M):
a, b = list(map(int, input().split()))
if a == 1:
transit[b] = True
if b == N:
transit2[a] = True
for i in range(N):
if transit[i] and transit2[i]:
print("POSSIBLE")
exit()
print("IMPOSSIBLE") | p03645 |
n,m = list(map(int,input().split()))
a_to = []
a_from = []
for i in range(m):
a,b = list(map(int,input().split()))
if a==1:
a_to.append(b)
if b==1:
a_to.append(a)
if a==n:
a_from.append(b)
if b==n:
a_from.append(a)
isOK = False
for j in range(len(a_to)):
if a_to[j] in a_from:
isOK = True
break
#print(a_to)
#print(a_from)
if isOK:
print('POSSIBLE')
else:
print('IMPOSSIBLE')
| n,m = list(map(int,input().split()))
#a_to = []
#a_from = []
dic = {}
isOK = False
for i in range(m):
a,b = list(map(int,input().split()))
if a in [1,n]:
dic.setdefault(b,0)
dic[b] += 1
if dic[b]==2:
isOK = True
break
elif b in [1,n]:
dic.setdefault(a,0)
dic[a] += 1
if dic[a]==2:
isOK = True
break
# if a==1:
# a_to.append(b)
# if b==1:
# a_to.append(a)
# if a==n:
# a_from.append(b)
# if b==n:
# a_from.append(a)
#for j in range(len(a_to)):
# if a_to[j] in a_from:
# isOK = True
# break
#print(a_to)
#print(a_from)
if isOK:
print('POSSIBLE')
else:
print('IMPOSSIBLE')
| p03645 |
#ABC068C
N,M=list(map(int,input().split()))
A=[]
B=[]
C=[]
D=[]
for m in range(M):
I=list(map(int,input().split()))
if I[0]==1:
A.append(I[0])
B.append(I[1])
if I[1]==N:
C.append(I[0])
D.append(I[1])
for b in B:
for c in C:
if b==c:
print('POSSIBLE')
exit()
print('IMPOSSIBLE') | #ABC068C
N,M=list(map(int,input().split()))
A=[]
B=[]
C=[]
D=[]
for m in range(M):
I=list(map(int,input().split()))
if I[0]==1:
A.append(I[0])
B.append(I[1])
elif I[1]==N:
C.append(I[0])
D.append(I[1])
if len(set(B)&set(C))>0:
print('POSSIBLE')
else:
print('IMPOSSIBLE') | p03645 |
import sys
n,m = list(map(int, sys.stdin.readline().split()))
ab = [[0, 0]]*m
for i in range(m):
ab[i] = list(map(int, sys.stdin.readline().split()))
tmp = []
for i in ab:
if i[0] == 1:
tmp.append(i[1])
tmp_n = []
for i in ab:
if i[1] == n:
tmp_n.append(i[0])
flag = False
for i in tmp:
if i in tmp_n:
flag = True
break
if flag:
print("POSSIBLE")
else:
print("IMPOSSIBLE")
| import sys
n,m = list(map(int, sys.stdin.readline().split()))
mid1 = set()
mid2 = set()
for _ in range(m):
a,b, = list(map(int, input().split()))
if a == 1:
mid1.add(b)
elif b == n:
mid2.add(a)
result = bool(mid1 & mid2)
if result:
print("POSSIBLE")
else:
print("IMPOSSIBLE")
| p03645 |
N, M = list(map(int, input().split()))
starts = []
goals = []
for _ in range(M):
s, g = list(map(int, input().split()))
if s == 1:
starts.append(g)
elif g == N:
goals.append(s)
for i in starts:
if i in goals:
print("POSSIBLE")
exit()
print("IMPOSSIBLE") | N, M = list(map(int, input().split()))
starts = []
goals = []
for _ in range(M):
s, g = list(map(int, input().split()))
if s == 1:
starts.append(g)
elif g == N:
goals.append(s)
ans = set(starts) & set(goals)
if len(ans) >= 1:
print("POSSIBLE")
else:
print("IMPOSSIBLE") | p03645 |
n,m=list(map(int,input().split()))
ab=[[int(i) for i in input().split()] for j in range(m)]
li=[[] for i in range(n+1)]
for a,b in ab:
li[a].append(b)
li2=[]
for i in li[1]:
li2.append(i)
ans=False
for i in li2:
if n in li[i]:
ans=True
print(('POSSIBLE' if ans else 'IMPOSSIBLE')) | import sys
input = sys.stdin.readline
n,m=list(map(int,input().split()))
ab=[[int(i) for i in input().split()] for j in range(m)]
li=[[] for i in range(n+1)]
for a,b in ab:
li[a].append(b)
li2=[]
for i in li[1]:
li2.append(i)
ans=False
for i in li2:
if n in li[i]:
ans=True
print(('POSSIBLE' if ans else 'IMPOSSIBLE')) | p03645 |
N, M = [int(i) for i in input().split()]
S, G = set(), set()
for _ in range(M):
a, b = [int(i) for i in input().split()]
if a == 1:
S.add(b)
if b == N:
G.add(a)
if any(s in G for s in S):
print("POSSIBLE")
else:
print("IMPOSSIBLE") | N, M = [int(i) for i in input().split()]
S, G = set(), set()
for _ in range(M):
a, b = [int(i) for i in input().split()]
if a == 1:
S.add(b)
if b == N:
G.add(a)
if len(S & G) >= 1:
print("POSSIBLE")
else:
print("IMPOSSIBLE") | p03645 |
N, M = [int(i) for i in input().split()]
S, G = set(), set()
for _ in range(M):
a, b = [int(i) for i in input().split()]
if a == 1:
S.add(b)
if b == N:
G.add(a)
if len(S & G) >= 1:
print("POSSIBLE")
else:
print("IMPOSSIBLE") | N, M = [int(i) for i in input().split()]
S, G = [False] * N, [False] * N
for _ in range(M):
a, b = [int(i) for i in input().split()]
if a == 1:
S[b - 1] = True
if b == N:
G[a - 1] = True
if any(s and g for s, g in zip(S, G)):
print("POSSIBLE")
else:
print("IMPOSSIBLE") | p03645 |
N, M = list(map(int, input().split()))
S = [[] for i in range(N)]
for i in range(M):
a, b = list(map(int, input().split()))
S[a-1].append(b-1)
S[b-1].append(a-1)
for b in S[0]:
if N-1 in S[b]:
print("POSSIBLE")
break
else:
print("IMPOSSIBLE") | N, M = list(map(int, input().split()))
S = [[] for i in range(N)]
for i in range(M):
a, b = list(map(int, input().split()))
S[a-1].append(b-1)
S[b-1].append(a-1)
print(("POSSIBLE" if set(S[0]) & set(S[N-1]) else "IMPOSSIBLE"))
| p03645 |
n,m = list(map(int,input().split()))
V = [[] for i in range(n+1)]
for i in range(m):
a,b = list(map(int,input().split()))
V[a].append(b)
V[b].append(a)
from collections import deque
q = deque([])
q.append(1)
reach = [0]*(n+1)
reach[0] = -1
while q:
x = q.popleft()
for v in V[x]:
if reach[v] == 0:
q.append(v)
reach[v] = reach[x]+1
if max(reach) >= 3:
break
if reach[-1] == 2:
print("POSSIBLE")
else:
print("IMPOSSIBLE") | n,m = list(map(int,input().split()))
V = [[] for i in range(n+1)]
for i in range(m):
a,b = list(map(int,input().split()))
V[a].append(b)
V[b].append(a)
W = V[1]
z = []
for x in W:
z.append(V[x])
s = 0
for q in z:
if n in q:
s = 1
break
if s == 1:
print("POSSIBLE")
else:
print("IMPOSSIBLE") | p03645 |
n,m = list(map(int,input().split()))
ab = [list(map(int,input().split())) for _ in range(m)]
ab.sort()
mid = []
cand = []
mid_id = 0
for i in range(m):
if ab[i][0] == 1:
mid.append(ab[i][1])
elif ab[i][0] == n or ab[i][1] == n:
cand.append(ab[i])
if len(mid) == 0:
print('IMPOSSIBLE')
exit()
for j in range(len(cand)):
if cand[j][0] in mid and cand[j][1] == n:
print('POSSIBLE')
exit()
elif cand[j][1] in mid and cand[j][0] == n:
print('POSSIBLE')
exit()
print('IMPOSSIBLE') | n,m = list(map(int,input().split()))
ab = [list(map(int,input().split())) for _ in range(m)]
ab.sort()
mid = []
cand = []
for i in range(m):
if ab[i][0] == 1:
mid.append(ab[i][1])
elif ab[i][0] == n:
cand.append(ab[i][1])
elif ab[i][1] == n:
cand.append(ab[i][0])
if len(set(mid) & set(cand)) > 0:
print('POSSIBLE')
else:
print('IMPOSSIBLE') | p03645 |
from collections import deque
n,m=[int(i) for i in input().split()]
a_to=deque([])
to_b=deque([])
for i in range(m):
a,b=[int(i) for i in input().split()]
if a==1:
a_to.append(b)
if b==n:
to_b.append(a)
for i in a_to:
if i in to_b:
print("POSSIBLE")
break
else:
print("IMPOSSIBLE") | n,m=[int(i) for i in input().split()]
a_to_b=[0]*n
for i in range(m):
a,b=[int(j) for j in input().split()]
if a==1:
a_to_b[b]+=1
if b==n:
a_to_b[a]+=1
if 2 in a_to_b:
print("POSSIBLE")
else:
print("IMPOSSIBLE") | p03645 |
import sys
sys.setrecursionlimit(200010)
def input():
return sys.stdin.readline()[:-1]
def main():
N, M = list(map(int,input().split()))
G = [[] for k in range(N)]
for i in range(M):
A, B = list(map(int,input().split()))
G[A-1].append(B-1)
G[B-1].append(A-1)
for e in G[0]:
if e in G[N-1]:
print("POSSIBLE")
exit(0)
print("IMPOSSIBLE")
if __name__ == '__main__':
main()
| import sys
sys.setrecursionlimit(200010)
def input():
return sys.stdin.readline()[:-1]
def main():
N, M = list(map(int,input().split()))
G = [set([]) for k in range(N)]
for i in range(M):
A, B = set(map(int,input().split()))
G[A-1].add(B-1)
G[B-1].add(A-1)
for e in G[0]:
if e in G[N-1]:
print("POSSIBLE")
exit(0)
print("IMPOSSIBLE")
if __name__ == '__main__':
main()
| p03645 |
N,M=list(map(int,input().split()))
L1=[]
LN=[]
for i in range(M):
a,b=list(map(int,input().split()))
if a==1:
if b in LN:
print("POSSIBLE")
exit()
else:
L1.append(b)
elif b==N:
if a in L1:
print("POSSIBLE")
exit()
else:
LN.append(a)
print("IMPOSSIBLE") | N,M=list(map(int,input().split()))
Start=[]
Goal=[]
for i in range(M):
a,b=list(map(int,input().split()))
if a==1:
Start.append(b)
elif b==1:
Start.append(a)
if a==N:
Goal.append(b)
elif b==N:
Goal.append(a)
S=set(Start)
G=set(Goal)
if len(S&G)>0:
print("POSSIBLE")
elif len(S&G)==0:
print("IMPOSSIBLE") | p03645 |
N,M = list(map(int, input().split()))
AB = [list(map(int, input().split())) for _ in range(M)]
first_to = []
to_dest = []
for ab in AB:
if ab[0] == 1:
first_to.append(ab[1])
elif ab[1] == N:
to_dest.append(ab[0])
for f in first_to:
if f in to_dest:
print('POSSIBLE')
break
else:
print('IMPOSSIBLE')
| N,M = list(map(int, input().split()))
AB = [list(map(int, input().split())) for _ in range(M)]
first_to = []
to_dest = []
for ab in AB:
if ab[0] == 1:
first_to.append(ab[1])
elif ab[1] == N:
to_dest.append(ab[0])
first_to = set(first_to)
to_dest = set(to_dest)
for f in first_to:
if f in to_dest:
print('POSSIBLE')
break
else:
print('IMPOSSIBLE')
| p03645 |
n,m=list(map(int,input().split()))
candidate = []
for i in range(m):
a,b=list(map(int,input().split()))
if a==1:
if b in candidate:
print('POSSIBLE')
exit()
else:
candidate.append(b)
if b==n:
if a in candidate:
print('POSSIBLE')
exit()
else:
candidate.append(a)
print('IMPOSSIBLE')
| n,m=list(map(int,input().split()))
from_1=[]
to_n=[]
for i in range(m):
a,b=list(map(int,input().split()))
if a==1:
from_1.append(b)
if b==n:
to_n.append(a)
if len(set(from_1) & set(to_n)) >= 1:
print('POSSIBLE')
else:
print('IMPOSSIBLE')
| p03645 |
import itertools
n,m=list(map(int,input().split()))
AB=[list(map(int,input().split())) for _ in range(m)]
for ship1,ship2 in list(itertools.combinations(AB,2)):
now=ship1[0]
if now==1:
now=ship1[1]
if now==ship2[0] and ship2[1]==n:
print('POSSIBLE')
exit()
now=ship2[0]
if now==1:
now=ship2[1]
if now==ship1[0] and ship1[1]==n:
print('POSSIBLE')
exit()
print('IMPOSSIBLE') | import itertools
n,m=list(map(int,input().split()))
AB=[list(map(int,input().split())) for _ in range(m)]
next=set()
for a,b in AB:
if a==1:
next.add(b)
for a,b in AB:
if a in next and b==n:
print('POSSIBLE')
exit()
print('IMPOSSIBLE') | p03645 |
import sys
n,m = list(map(int,input().split()))
a = [list(map(int,input().split())) for _ in range(m)]
start = a[0][0]
goal = n
tmp,ans = [],[]
for i in range(m):
if a[i][1] == goal:
tmp.append(a[i][0])
#print(tmp)
for j in range(m):
if a[j][0] == start:
if a[j][1] in tmp:
print('POSSIBLE')
sys.exit()
print('IMPOSSIBLE')
| import sys
n,m = list(map(int,input().split()))
a = [list(map(int,input().split())) for _ in range(m)]
start = a[0][0]
goal = n
tmp,ans = [],[]
for i in range(m):
if a[i][1] == goal:
tmp.append(a[i][0])
#print(tmp)
for j in range(m):
if a[j][0] == start:
ans.append(a[j][1])
if len(set(tmp)&set(ans)) > 0:
print('POSSIBLE')
sys.exit()
print('IMPOSSIBLE') | p03645 |
n,m = list(map(int,input().split()))
li = [[0 for _ in range(n)] for _ in range(n)]
for i in range(m):
a,b = list(map(int,input().split()))
a-=1
b-=1
li[a][b] = 1
li[b][a] = 1
ans = False
for i in range(1,n-1):
if li[0][i] and li[i][n-1]:
ans = True
break
if ans:
print("POSSIBLE")
else:
print("IMPOSSIBLE") | n,m = list(map(int,input().split()))
li1 = [0 for _ in range(n)]
li2 = [0 for _ in range(n)]
for i in range(m):
a,b = list(map(int,input().split()))
a-=1
b-=1
if a==0:
li1[b] = 1
elif b==n-1:
li2[a] = 1
ans = False
for i in range(1,n-1):
if li1[i] and li2[i]:
ans = True
break
if ans:
print("POSSIBLE")
else:
print("IMPOSSIBLE") | p03645 |
n,m=list(map(int,input().split()))
a,b=[0]*m,[0]*m
for i in range(m):
a[i],b[i] = list(map(int,input().split()))
for i in range(m):
if a[i]==1:
p=b[i]
for j in range(m):
if a[j]==p and b[j]==n:
print('POSSIBLE')
exit()
print('IMPOSSIBLE') | n,m=list(map(int,input().split()))
a,b=[0]*m,[0]*m
c=[False]*(n+1)
d=[False]*(n+1)
for i in range(m):
a[i],b[i] = list(map(int,input().split()))
if a[i]==1: c[b[i]]=True
if b[i]==n: d[a[i]]=True
for i in range(n):
if c[i] and d[i]:
print('POSSIBLE')
exit()
print('IMPOSSIBLE') | p03645 |
from collections import deque
def bfs(graph:list, node:int, start:int) -> list:
# 未探索のノードは距離INF
INF = float("inf")
dist = [INF]*node
# 始点ノードの距離を0とし、dfsのためのstackを作成
dist[start] = 0
que = deque([(0,start)])
# 未探索のノードをqueueに入れる
while que:
cost, cur_node = que.popleft()
for nex_cost, nex_node in graph[cur_node]:
if dist[nex_node] != INF:
continue
else:
dist[nex_node] = dist[cur_node] + nex_cost
que.append((dist[nex_node], nex_node))
return dist
N,M = list(map(int, input().split()))
AB = []
for i in range(M):
AB.append(tuple(map(int, input().split())))
#N,M = 4,3
#AB = [(1,2),(2,3),(3,4)]
adj_list = [[] for _ in range(N)]
for a,b in AB:
a -= 1
b -= 1
adj_list[a].append((1,b))
adj_list[b].append((1,a))
dist = bfs(adj_list, N, 0)
if dist[N-1] == 2:
print("POSSIBLE")
else:
print("IMPOSSIBLE") | import sys
sdin = sys.stdin.readline
N,M = list(map(int, sdin().split()))
AB = []
for i in range(M):
AB.append(tuple(map(int, sdin().split())))
to_mid = set()
from_mid = set()
for a,b in AB:
if a==1:
to_mid.add(b)
if b==N:
from_mid.add(a)
if to_mid & from_mid:
print("POSSIBLE")
else:
print("IMPOSSIBLE")
| p03645 |
N,M = list(map(int,input().split()))
onelist,nlist = [],[]
for i in range(M):
aa,bb = list(map(int,input().split()))
if aa == 1:
onelist.append(bb)
if bb == N:
nlist.append(aa)
for b in onelist:
if b in nlist:
print("POSSIBLE")
exit()
print("IMPOSSIBLE")
| N,M = list(map(int,input().split()))
onelist,nlist = [],[]
for i in range(M):
aa,bb = list(map(int,input().split()))
if aa == 1:
onelist.append(bb)
if bb == N:
nlist.append(aa)
if len(set(onelist) & set(nlist)) == 0:
print("IMPOSSIBLE")
else:
print("POSSIBLE")
| p03645 |
import heapq
INFTY = 1e6
N,M = list(map(int,input().split()))
G = {}
for _ in range(M):
a,b = list(map(int,input().split()))
if a not in G:
G[a] = []
G[a].append(b)
if b not in G:
G[b] = []
G[b].append(a)
d = [INFTY for _ in range(N+1)]
hist = [0 for _ in range(N+1)]
heap = [(0,1)]
d[1] = 0
while heap:
cur = heapq.heappop(heap)
hist[cur[1]] = 1
for x in G[cur[1]]:
if hist[x]==0:
if d[x]>cur[0]+1:
d[x] = cur[0]+1
heapq.heappush(heap,(d[x],x))
if d[N]==2:
print("POSSIBLE")
else:
print("IMPOSSIBLE") | import heapq
INFTY = 10**6
N,M = list(map(int,input().split()))
G = {i:[] for i in range(1,N+1)}
for _ in range(M):
a,b = list(map(int,input().split()))
G[a].append(b)
G[b].append(a)
dist = [INFTY for _ in range(N+1)]
hist = [0 for _ in range(N+1)]
heap = [(0,1)]
dist[1] = 0
hist[1] = 1
while heap:
d,x = heapq.heappop(heap)
if dist[x]<d:continue
hist[x]=1
for y in G[x]:
if hist[y]==0 and dist[y]>d+1:
dist[y] = d+1
heapq.heappush(heap,(d+1,y))
if dist[N]==2:
print("POSSIBLE")
else:
print("IMPOSSIBLE") | p03645 |
import math
from math import gcd,pi,sqrt
INF = float("inf")
import sys
sys.setrecursionlimit(10**6)
import itertools
from collections import Counter,deque
def i_input(): return int(eval(input()))
def i_map(): return list(map(int, input().split()))
def i_list(): return list(i_map())
def i_row(N): return [i_input() for _ in range(N)]
def i_row_list(N): return [i_list() for _ in range(N)]
def s_input(): return eval(input())
def s_map(): return input().split()
def s_list(): return list(s_map())
def s_row(N): return [s_input for _ in range(N)]
def s_row_str(N): return [s_list() for _ in range(N)]
def s_row_list(N): return [list(s_input()) for _ in range(N)]
import string
def main():
n,m = i_map()
c = [[INF]*n for _ in range(n)]
for i in range(n):
c[i][i] = 0
for _ in range(m):
a,b = i_map()
c[a-1][b-1] = 1
c[b-1][a-1] = 1
for i,k in enumerate(c[0]):
pass
if k == 1:
if c[i][-1] == 1:
print("POSSIBLE")
exit()
print("IMPOSSIBLE")
if __name__=="__main__":
main()
| N, M = list(map(int, input().split()))
L = [list(map(int, input().split())) for i in range(M)]
s = []
g = []
for i in range(M):
if 1 == L[i][0]:
s.append(L[i][1])
if 1 == L[i][1]:
s.append(L[i][0])
for i in range(M):
if N == L[i][0]:
g.append(L[i][1])
if N == L[i][1]:
g.append(L[i][0])
if set(g)&set(s):
print('POSSIBLE')
else:
print('IMPOSSIBLE')
| p03645 |
import math
from math import gcd,pi,sqrt
INF = float("inf")
import sys
sys.setrecursionlimit(10**6)
import itertools
from collections import Counter,deque
def i_input(): return int(eval(input()))
def i_map(): return list(map(int, input().split()))
def i_list(): return list(i_map())
def i_row(N): return [i_input() for _ in range(N)]
def i_row_list(N): return [i_list() for _ in range(N)]
def s_input(): return eval(input())
def s_map(): return input().split()
def s_list(): return list(s_map())
def s_row(N): return [s_input for _ in range(N)]
def s_row_str(N): return [s_list() for _ in range(N)]
def s_row_list(N): return [list(s_input()) for _ in range(N)]
import string
def main():
n,m = i_map()
c = [[INF]*n for _ in range(n)]
for i in range(n):
c[i][i] = 0
for _ in range(m):
a,b = i_map()
c[a-1][b-1] = 1
c[b-1][a-1] = 1
for i,k in enumerate(c[0]):
if k == 1:
if c[i][-1] == 1:
print("POSSIBLE")
exit()
print("IMPOSSIBLE")
if __name__=="__main__":
main()
| import math
from math import gcd,pi,sqrt
INF = float("inf")
import sys
sys.setrecursionlimit(10**6)
import itertools
from collections import Counter,deque
def i_input(): return int(eval(input()))
def i_map(): return list(map(int, input().split()))
def i_list(): return list(i_map())
def i_row(N): return [i_input() for _ in range(N)]
def i_row_list(N): return [i_list() for _ in range(N)]
def s_input(): return eval(input())
def s_map(): return input().split()
def s_list(): return list(s_map())
def s_row(N): return [s_input for _ in range(N)]
def s_row_str(N): return [s_list() for _ in range(N)]
def s_row_list(N): return [list(s_input()) for _ in range(N)]
import string
def main():
n,m = i_map()
s = set()
g = set()
for _ in range(m):
a,b = i_map()
if a == 1:
s.add(b)
elif b == 1:
s.add(a)
elif a == n:
g.add(b)
elif b == n:
g.add(a)
if s&g:
print("POSSIBLE")
else:
print("IMPOSSIBLE")
if __name__=="__main__":
main()
| p03645 |
n, m = list(map(int, input().split()))
ship = {i:[] for i in range(1, n+1)}
for _ in range(m):
a, b = list(map(int, input().split()))
ship[a].append(b)
for i in ship[1]:
if n in ship[i]:
print("POSSIBLE")
exit()
print("IMPOSSIBLE") | n, m = list(map(int, input().split()))
ship = {i:False for i in range(1, n+1)}
bl = []
for _ in range(m):
a, b = list(map(int, input().split()))
if a == 1:
ship[b] = True
elif b == n:
bl.append(a)
for i in bl:
if ship[i] == True:
print("POSSIBLE")
exit()
print("IMPOSSIBLE") | p03645 |
n,m=list(map(int,input().split()))
l=[list(map(int,input().split())) for i in range(m)]
#print(n,m,l)
def bin_search(a,li):
max_len=len(li)
min_len=0
while max_len>min_len:
mid=(max_len+min_len)//2
if li[mid]==a:
return True
elif abs(min_len-max_len)==1 and min_len>=0 and li[min_len]!=a and max_len<len(li) and li[max_len]!=a:
break
elif li[mid]<a:
min_len=mid
else:
max_len=mid
s=[]
g=[]
for i in l:
if i[0]==1:
s.append(i[1])
if i[1]==n:
g.append(i[0])
g.sort
for i in s:
if bin_search(i,g):
print('POSSIBLE')
break
else:
print('IMPOSSIBLE') | n,m=list(map(int,input().split()))
l=[list(map(int,input().split())) for i in range(m)]
#print(n,m,l)
def bin_search(a,li):
max_len=len(li)-1
min_len=0
while max_len>=min_len:
mid=(max_len+min_len)//2
if li[mid]==a:
return True
elif li[mid]<a:
min_len=mid+1
else:
max_len=mid-1
s=[]
g=[]
for i in l:
if i[0]==1:
s.append(i[1])
if i[1]==n:
g.append(i[0])
g.sort()
for i in s:
if bin_search(i,g):
print('POSSIBLE')
break
else:
print('IMPOSSIBLE') | p03645 |
N,M = list(map(int,input().split()))
li = [tuple(map(int,input().split())) for i in range(M)]
numb = [li[i][1] for i in range(M) if li[i][0] == 1]
ans = ''
for i in range(M):
if li[i][0] in numb and li[i][1] == N:
ans = 'POSSIBLE'
break
if ans == '':
print('IMPOSSIBLE')
else:
print(ans)
| N,M = list(map(int,input().split()))
li = []
numb = []
for i in range(M):
a,b = list(map(int,input().split()))
if a == 1:
li.append(b)
elif b == N:
numb.append(a)
ans = set(li) & set(numb)
if len(ans) >= 1:
print('POSSIBLE')
else:
print('IMPOSSIBLE') | p03645 |
N, M = list(map(int, input().split()))
X = []
Y = []
for i in range(M):
S, E = list(map(int, input().split()))
if S == 1:
X.append(E)
if E == N:
Y.append(S)
while 1:
if X == [] or Y == []:
print("IMPOSSIBLE")
break
min_x = min(X)
min_y = min(Y)
if min_x == min_y:
print("POSSIBLE")
break
elif min_x > min_y:
Y.remove(min_y)
elif min_x < min_y:
X.remove(min_x)
else:
print("IMPOSSIBLE")
| N, M = list(map(int, input().split()))
X = [0] * N
Y = [0] * N
for i in range(M):
S, E = list(map(int, input().split()))
if S == 1:
X[E-1] = 1
if E == N:
Y[S-1] = 1
for i in range(N):
if X[i] == 1 and Y[i] == 1:
print("POSSIBLE")
break
else:
print("IMPOSSIBLE")
| p03645 |
N, M = list(map(int, input().split()))
a = [0]*M
b = [0]*M
for i in range(M):
a[i], b[i] = list(map(int, input().split()))
if N in b and 1 in a:
for i in range(M):
for j in range(M):
if a[j] == 1 and b[i] == N and a[i] == b[j]:
print('POSSIBLE')
exit()
else:
pass
print('IMPOSSIBLE') | n, m = list(map(int, input().split()))
d = {i:[] for i in range(1, n)}
for i in range(m):
a, b = list(map(int, input().split()))
d[a].append(b)
ans = "IMPOSSIBLE"
for dd in d[1]:
if n in d[dd]:
ans = "POSSIBLE"
break
print(ans) | p03645 |
import sys
l = list(map(int, input().split(' ')))
N = l[0]
N_ = l[0] + 1
M = l[1]
y = []
u = []
for i in range(M):
k = list(map(int, input().split()))
a = k[0]
b = k[1]
if (a == 1):
y.append(b)
elif (b == N):
u.append(a)
for i in y:
if (i in u):
print('POSSIBLE')
sys.exit()
print('IMPOSSIBLE')
| import sys
l = list(map(int, input().split(' ')))
N = l[0]
N_ = l[0] + 1
M = l[1]
y = []
u = set()
for i in range(M):
k = list(map(int, input().split()))
a = k[0]
b = k[1]
if (a == 1):
y.append(b)
elif (b == N):
u.add(a)
for i in y:
if (i in u):
print('POSSIBLE')
sys.exit()
print('IMPOSSIBLE')
| p03645 |
n,m = list(map(int,input().split()))
s = [[int(i) for i in input().split()] for i in range(m)]
d = {}
for i in range(m):
if s[i][0] == 1:
d[s[i][1]] = 1
for i in range(m):
if s[i][1] == n and s[i][0] in d:
print("POSSIBLE")
exit()
print("IMPOSSIBLE") | n,m = list(map(int,input().split()))
d1 = {}
d2 = {}
for i in range(m):
a,b = list(map(int,input().split()))
if a == 1: d1[b] = 1
if b == n: d2[a] = 1
for k in d1:
if k in d2:
ans = "POSSIBLE"
break
else:
ans = "IMPOSSIBLE"
print(ans) | p03645 |
N, M = list(map(int, input().split()))
check_1 = []
check_N = []
for i in range(M):
a, b = list(map(int, input().split()))
if a == 1:
check_1.append(b)
if b == N:
check_N.append(a)
check_1 = list(set(check_1))
chek_N = list(set(check_N))
flag = False
for i in sorted(check_1):
if i in check_N:
flag = True
break
if flag:
print('POSSIBLE')
else:
print('IMPOSSIBLE') | N, M = list(map(int, input().split()))
check_1 = []
check_N = []
for i in range(M):
a, b = list(map(int, input().split()))
if a == 1:
check_1.append(b)
if b == N:
check_N.append(a)
if len(list(set(check_1) & set(check_N))) > 0:
print('POSSIBLE')
else:
print('IMPOSSIBLE') | p03645 |
# coding: utf-8
N,M=list(map(int,input().split()))
L=[]
B=[]
flg=0
cnt=0
for i in range(M):
a,b=list(map(int,input().split()))
L.append([a,b])
if a==1:
B.append(b)
cnt+=1
#print(L)
ans=[]
for i in range(M):
for j in range(cnt):
if L[i][0]==B[j]:
ans.append(L[i][1])
#print(ans)
if N in ans:
print('POSSIBLE')
else:
print('IMPOSSIBLE') | # coding: utf-8
N,M=list(map(int,input().split()))
L=[]
B=[]
A=[]
flg=0
cnt=0
for i in range(M):
a,b=list(map(int,input().split()))
L.append([a,b])
if a==1:
B.append(b)
cnt+=1
elif b==N:
A.append(a)
#print(L)
ans=[]
if len(set(A)&set(B))==0:
print('IMPOSSIBLE')
else:
print('POSSIBLE') | p03645 |
n,m=list(map(int,input().split()))
A=[]
B=[]
for i in range(m):
a,b=list(map(int,input().split()))
if a==1:
A.append(b)
if b==n:
B.append(a)
for i in A:
if i in B:
print("POSSIBLE")
break
else:
print("IMPOSSIBLE") | n,m=list(map(int,input().split()))
A=[]
B=[]
for i in range(m):
a,b=list(map(int,input().split()))
if a==1:
A.append(b)
if b==n:
B.append(a)
if len(set(A) & set(B))>0:
print("POSSIBLE")
else:
print("IMPOSSIBLE") | p03645 |
# -*- coding:utf-8 -*-
def solve():
N, M = list(map(int, input().split()))
"""
from1 := 1から行ける島番号のリスト
toN := Nに行ける島番号のリスト
from1とtoNの両方に同じ島番号が存在するとき、POSSIBLE
"""
from1, toN = [], []
for i in range(M):
a, b = list(map(int, input().split()))
if a == 1:
from1.append(b)
elif b == N:
toN.append(a)
for b in from1:
if b in toN:
print("POSSIBLE")
return
print("IMPOSSIBLE")
if __name__ == "__main__":
solve()
| # -*- coding:utf-8 -*-
def solve():
N, M = list(map(int, input().split()))
"""
from1 := 1から行ける島番号のリスト
canN[i] := 島iがNに行くことができるか否か
from1とtoNの両方に同じ島番号が存在するとき、POSSIBLE
"""
from1 = []
canN = [False] * (N+1)
for i in range(M):
a, b = list(map(int, input().split()))
if a == 1:
from1.append(b)
elif b == N:
canN[a] = True
for b in from1:
if canN[b]:
print("POSSIBLE")
return
print("IMPOSSIBLE")
if __name__ == "__main__":
solve()
| p03645 |
#2問目
# resultにそれぞれの深さの数を入れていく
N, M = list(map(int, input().split()))
link = [[] for i in range(N)]
for i in range(M):
A, B = list(map(int, input().split()))
link[A-1].append(B-1)
link[B-1].append(A-1)
visited = [-1 for i in range(N)]
Q = [0]
visited[0] = 0
#Qに要素がなくなるまで
while Q:
#一番上の要素をpop
v = Q.pop(0)
for i in link[v]:
if visited[i] == -1:
visited[i] = visited[v] + 1
Q.append(i)
if 0 <= visited[N-1] <= 2: print("POSSIBLE")
else: print("IMPOSSIBLE") | #2問目
N, M = list(map(int, input().split()))
link1 = [False for i in range(N+1)]
link2 = [False for i in range(N+1)]
flag = False
for i in range(M):
A, B = list(map(int, input().split()))
if A == 1:
link1[B] = True
elif B == N:
link2[A] = True
for i in range(2, N):
if link1[i] and link2[i]:
print("POSSIBLE")
flag = True
break
if flag == False:
print("IMPOSSIBLE") | p03645 |
n, m = list(map(int, input().split()))
root_map = dict()
root_map[1] = set()
root_map[n] = set()
for i in range(m):
a, b = list(map(int, input().split()))
if a not in root_map:
root_map[a] = set()
root_map[a].add(b)
else:
root_map[a].add(b)
if b not in root_map:
root_map[b] = set()
root_map[b].add(a)
else:
root_map[b].add(a)
for i in root_map[1]:
if i in root_map[n]:
print("POSSIBLE")
break
else:
print("IMPOSSIBLE")
| n, m = list(map(int, input().split()))
root_map = dict()
root_map[1] = set()
root_map[n] = set()
for i in range(m):
a, b = list(map(int, input().split()))
if a == 1 or a == n:
root_map[a].add(b)
if b == 1 or b == n:
root_map[b].add(a)
for i in root_map[1]:
if i in root_map[n]:
print("POSSIBLE")
break
else:
print("IMPOSSIBLE")
| p03645 |
N, M = list(map(int, input().split()))
c = []
for i in range(M):
c.append(list(map(int, input().split())))
for i in range(M):
if c[i][0] == 1:
for j in range(M):
if c[j][0] == c[i][1]:
if c[j][1] == N:
print('POSSIBLE')
exit()
print('IMPOSSIBLE') | N, M = list(map(int, input().split()))
c = []
for i in range(M):
c.append(list(map(int, input().split())))
d = []
e = []
for i in range(M):
if c[i][0] == 1:
d.append(c[i][1])
for i in range(M):
if c[i][1] == N:
e.append(c[i][0])
l = list(set(d) & set(e))
if l == []:
print('IMPOSSIBLE')
else:
print('POSSIBLE') | p03645 |
N, M = list(map(int, input().split()))
ab = [list(map(int, input().split())) for _ in range(M)]
S = []
E = []
for i in range(M):
if ab[i][0] == 1:
S.append(ab[i][1])
if ab[i][1] == N:
E.append(ab[i][0])
#print(S)
#print(E)
flag = False
for s in S:
if s in E:
flag = True
break
if flag:
print('POSSIBLE')
else:
print('IMPOSSIBLE')
| N, M = list(map(int, input().split()))
ab = [list(map(int, input().split())) for _ in range(M)]
S = []
E = []
for i in range(M):
if ab[i][0] == 1:
S.append(ab[i][1])
if ab[i][1] == N:
E.append(ab[i][0])
if set(S) & set(E):
print('POSSIBLE')
else:
print('IMPOSSIBLE')
| p03645 |
N, M = list(map(int,input().split()))
ships = []
for m in range(M):
ships.append(list(map(int,input().split())))
flag = 0
for n in range(2,N+1):
if [1,n] in ships and [n,N] in ships:
print("POSSIBLE")
flag=1
break
if flag==0:
print("IMPOSSIBLE")
| N, M = list(map(int,input().split()))
ships_1 = []
ships_2 = []
for m in range(M):
tmp = list(map(int,input().split()))
if tmp[0]==1:
ships_1.append(tmp[1])
elif tmp[1] == N:
ships_2.append(tmp[0])
matched_list = list(set(ships_1) & set(ships_2))
if matched_list:
print("POSSIBLE")
else:
print("IMPOSSIBLE")
| p03645 |
N,M=list(map(int,input().split()))
l,r=[],[]
for i in range(M):
a,b=list(map(int,input().split()))
if a==1:l.append([a,b])
if b==N:r.append([a,b])
for i in l:
for j in r:
if i[1]==j[0]:
print('POSSIBLE')
exit()
print('IMPOSSIBLE') | N,M=list(map(int,input().split()))
l,r=[0]*N,[0]*N
for i in range(M):
a,b=list(map(int,input().split()))
if a==1:
l[b-1]=1
if b==N:
r[a-1]=1
for i in range(N):
if l[i]+r[i]==2:
print('POSSIBLE')
exit()
print('IMPOSSIBLE') | p03645 |
N, M = list(map(int, input().split()))
A = [0 for i in range(200000+1)]
B = [0 for i in range(200000+1)]
ans = 'IMPOSSIBLE'
for i in range(M):
a, b = list(map(int, input().split()))
if a == 1:
A[b] = 1
if A[b] and B[b]:
ans = 'POSSIBLE'
break
elif b == N:
B[a] = 1
if A[a] and B[a]:
ans = 'POSSIBLE'
break
print(ans) | N, M = list(map(int, input().split()))
A = set()
B = set()
for i in range(M):
a, b = list(map(int, input().split()))
if a == 1:
A.add(b)
elif b == N:
B.add(a)
if len(A & B):
print('POSSIBLE')
else:
print('IMPOSSIBLE') | p03645 |
from collections import deque
N, M = list(map(int, input().split()))
lst = [[] for _ in range(N + 1)]
dist = [float("inf")]*(N+1)
for _ in range(M):
a, b = list(map(int, input().split()))
lst[a].append(b)
lst[b].append(a)
q = deque()
d = 0
q.append([1,d])
while q:
now, d = q.popleft()
dist[now] = d
if now == N:
if d <= 2:
print("POSSIBLE")
else:
print("IMPOSSIBLE")
exit()
for itm in lst[now]:
if dist[itm] > d+1:
q.append([itm,d+1])
print("IMPOSSIBLE") | from collections import deque
N, M = map(int, input().split())
lst = [[] for _ in range(N + 1)]
dist = [float("inf")]*(N+1)
for _ in range(M):
a, b = map(int, input().split())
lst[a].append(b)
lst[b].append(a)
q = deque()
d = 0
q.append([1,d])
while q:
now, d = q.popleft()
dist[now] = d
for itm in lst[now]:
if dist[itm] > d+1:
q.append([itm,d+1])
print("POSSIBLE") if dist[N] <= 2 else print("IMPOSSIBLE")
| p03645 |
from collections import deque
N, M = map(int, input().split())
lst = [[] for _ in range(N + 1)]
dist = [float("inf")]*(N+1)
for _ in range(M):
a, b = map(int, input().split())
lst[a].append(b)
lst[b].append(a)
q = deque()
d = 0
q.append([1,d])
while q:
now, d = q.popleft()
dist[now] = d
for itm in lst[now]:
if dist[itm] > d+1:
q.append([itm,d+1])
print("POSSIBLE") if dist[N] <= 2 else print("IMPOSSIBLE")
| from collections import deque
N, M = map(int, input().split())
lst = [[] for _ in range(N + 1)]
dist = [float("inf")]*(N+1)
dist[1] = 0
for _ in range(M):
a, b = map(int, input().split())
lst[a].append(b)
lst[b].append(a)
q = deque()
q.append(1)
while q:
now = q.popleft()
for itm in lst[now]:
if dist[itm] > dist[now]:
q.append(itm)
dist[itm] = dist[now] + 1
print("POSSIBLE") if dist[N] <= 2 else print("IMPOSSIBLE")
| p03645 |
n, m = list(map(int, input().split()))
ikeru = [[] for _ in range(n)]
for i in range(m):
a, b = list(map(int, input().split()))
ikeru[a-1].append(b-1)
ikeru[b-1].append(a-1)
fukasa = [10**18 for _ in range(n)]
kaisuu = 0
settansaku = set([])
listmada = [0]
setmada = set([0])
while len(setmada) != 0:
kaisuu += 1
for i in listmada[:]:
settansaku.add(i)
listmada.remove(i)
setmada.remove(i)
for k in ikeru[i]:
if not k in setmada:
if not k in settansaku:
listmada.append(k)
setmada.add(k)
fukasa[k] = kaisuu
if fukasa[n-1] <= 2:
print("POSSIBLE")
else:
print("IMPOSSIBLE") | n, m = list(map(int, input().split()))
ikeru = [[] for _ in range(n)]
for i in range(m):
a, b = list(map(int, input().split()))
ikeru[a-1].append(b-1)
ikeru[b-1].append(a-1)
fukasa = [10**18 for _ in range(n)]
kaisuu = 0
settansaku = set([])
setmada = set([0])
while len(setmada) != 0:
kaisuu += 1
for i in list(setmada):
settansaku.add(i)
setmada.remove(i)
for k in ikeru[i]:
if not k in setmada:
if not k in settansaku:
setmada.add(k)
fukasa[k] = kaisuu
if fukasa[n-1] <= 2:
print("POSSIBLE")
else:
print("IMPOSSIBLE") | p03645 |
n, m = list(map(int, input().split()))
ab = [list(map(int, input().split())) for _ in range(m)]
ab1 = []
ab2 = []
for i in ab:
if i[0] == 1:
ab1.append(i[1])
elif i[1] == n:
ab2.append(i[0])
for i in ab1:
for j in ab2:
if i == j:
print("POSSIBLE")
exit()
print("IMPOSSIBLE") | n, m = list(map(int, input().split()))
ab = [list(map(int, input().split())) for _ in range(m)]
ab1 = []
ab2 = []
for i in ab:
if i[0] == 1:
ab1.append(i[1])
elif i[1] == n:
ab2.append(i[0])
jud = ab1 + ab2
if len(jud) == len(set(jud)):
print("IMPOSSIBLE")
else:
print("POSSIBLE")
| p03645 |
n,m = (int(i) for i in input().split())
x = [[int(i) for i in input().split()] for i in range(m)]
x.sort()
a = []
for i in x:
if i[0]==1:
a.append(i[1])
else:
break
for j in a:
if [j,n] in x:
m = 0
print("POSSIBLE")
break
if m != 0:
print("IMPOSSIBLE") | n,m = (int(i) for i in input().split())
x = [[int(i) for i in input().split()] for i in range(m)]
a ,b= [],[]
for i in x:
if i[0]==1:
a.append(i[1])
if i[1]==n:
b.append(i[0])
if len(a)+len(b) == len(set(a+b)): print("IMPOSSIBLE")
else: print("POSSIBLE") | p03645 |
# coding: utf-8
from queue import Queue
N, M = tuple(map(int, input().split()))
graph = [ [] for i in range(N+1)]
for i in range(M):
a, b = tuple(map(int, input().split()))
graph[a].append(b)
graph[b].append(a)
def is_reach(n):
dist = [0 for i in range(N+1)]
is_visit = [False for i in range(N+1)]
is_visit[1] = True
q = Queue()
q.put(1)
while not q.empty():
v = q.get()
for u in graph[v]:
if not is_visit[u]:
is_visit[u] = True
q.put(u)
dist[u] = dist[v] + 1
if u == n and dist[u] == 2:
return True
if dist[u] > 2:
return False
return False
print(("POSSIBLE" if is_reach(N) else "IMPOSSIBLE"))
| # coding: utf-8
N, M = tuple(map(int, input().split()))
graph = [ [] for i in range(N+1)]
for i in range(M):
a, b = tuple(map(int, input().split()))
graph[a].append(b)
graph[b].append(a)
res = "IMPOSSIBLE"
for i in range(2, N):
if 1 in graph[i] and N in graph[i]:
res = "POSSIBLE"
print(res)
| p03645 |
# /usr/bin/python
# -*- coding: utf-8 -*-
import math
def main():
N,M = list(map(int, input().split()))
route1 = []
routeN = []
for _ in range(M):
ab = sorted(list(map(int, input().split())))
if ab[0] == 1:
route1.append(ab[1])
elif ab[1] == N:
routeN.append(ab[0])
for i in route1:
if i in routeN:
return True
return False
if __name__ == "__main__":
if main():
print('POSSIBLE')
else:
print('IMPOSSIBLE') | # /usr/bin/python
# -*- coding: utf-8 -*-
import math
def main():
N,M = list(map(int, input().split()))
route = [0 for _ in range(N+1)]
for _ in range(M):
a,b = list(map(int, input().split()))
if a == 1:
route[b] += 1
elif b == N:
route[a] += 1
if max(route) >= 2:
return True
else:
return False
if __name__ == "__main__":
if main():
print('POSSIBLE')
else:
print('IMPOSSIBLE')
| p03645 |
N,M = list(map(int,input().split()))
K=[]
A=[]
B=[]
answer='IMPOSSIBLE'
for i in range(M):
a,b=list(map(int,input().split()))
if a==1:
A +=[b]
if b==N:
B += [a]
for x in B:
if x in A:
answer='POSSIBLE'
print(answer) | N,M = list(map(int,input().split()))
K=[0]*(N+1)
for i in range(M):
a,b=list(map(int,input().split()))
if a==1:
K[b] +=1
if b == N:
K[a] +=1
print(('POSSIBLE' if 2 in K else 'IMPOSSIBLE')) | p03645 |
n, m = list(map(int, input().split()))
a = []
b = []
for i in range(m):
a_, b_ = list(map(int, input().split()))
if a_ == 1 or a_ == n or b_ == 1 or b_ == n:
a.append(a_)
b.append(b_)
for i in range(len(a)):
if a[i] == 1 or b[i] == 1:
x = max(a[i], b[i])
for j in range(len(a)):
if a[j] == x or b[j] == x:
if max(a[j], b[j]) == n:
print("POSSIBLE")
exit()
print("IMPOSSIBLE")
| n, m = list(map(int, input().split()))
a = []
b = []
for i in range(m):
a_, b_ = list(map(int, input().split()))
if a_ == 1 or a_ == n or b_ == 1 or b_ == n:
a.append(a_)
b.append(b_)
x_min=[]
x_max=[]
for i in range(len(a)):
if a[i] == 1 or b[i] == 1:
x_max.append(max(a[i], b[i]))
if a[i] == n or b[i] == n:
x_min.append(min(a[i], b[i]))
x = x_min + x_max
if len(x) == len(set(x)):
print("IMPOSSIBLE")
else:
print("POSSIBLE")
| p03645 |
n, m = list(map(int, input().split()))
Ton = []
Fr1 = []
for i in range(m):
a, b = list(map(int, input().split()))
if b==n:
Ton.append(a)
if a==1:
Fr1.append(b)
r = 'IMPOSSIBLE'
for a in Fr1:
if a in Ton:
r = 'POSSIBLE'
print(r) | def main():
n, m = list(map(int, input().split()))
Ton, Fr1 = set(), set()
for _ in range(m):
a, b = list(map(int, input().split()))
if b==n:
Ton.add(a)
if a==1:
Fr1.add(b)
print(('POSSIBLE' if Ton&Fr1 else 'IMPOSSIBLE'))
main() | p03645 |
def slove():
import sys
import collections
input = sys.stdin.readline
n, m = list(map(int, input().rstrip('\n').split()))
s = collections.defaultdict(list)
e = collections.defaultdict(list)
for i in range(m):
a, b = list(map(int, input().rstrip('\n').split()))
if a == 1:
s[b]
if b == 1:
s[a]
if a == n:
e[b]
if b == n:
e[a]
for v in list(s.keys()):
if v in e:
print("POSSIBLE")
exit()
print("IMPOSSIBLE")
if __name__ == '__main__':
slove()
| import sys
import collections
def solve():
sys.setrecursionlimit(2000)
input = sys.stdin.readline
mod = 10 ** 9 + 7
n, m = list(map(int, input().rstrip('\n').split()))
d = collections.defaultdict(list)
for i in range(m):
a, b = list(map(int, input().rstrip('\n').split()))
if a == 1:
d[b] += [1]
if b == 1:
d[a] += [1]
if a == n:
d[b] += [n]
if b == n:
d[a] += [n]
for k, v in list(d.items()):
if len(v) == 2:
print("POSSIBLE")
exit()
print("IMPOSSIBLE")
if __name__ == '__main__':
solve()
| p03645 |
import sys
import collections
def solve():
sys.setrecursionlimit(2000)
input = sys.stdin.readline
mod = 10 ** 9 + 7
n, m = list(map(int, input().rstrip('\n').split()))
d = collections.defaultdict(list)
for i in range(m):
a, b = list(map(int, input().rstrip('\n').split()))
if a == 1:
d[b] += [1]
if b == 1:
d[a] += [1]
if a == n:
d[b] += [n]
if b == n:
d[a] += [n]
for k, v in list(d.items()):
if len(v) == 2:
print("POSSIBLE")
exit()
print("IMPOSSIBLE")
if __name__ == '__main__':
solve()
| import sys
import collections
def solve():
readline = sys.stdin.buffer.readline
mod = 10 ** 9 + 7
n, m = list(map(int, readline().split()))
d = collections.defaultdict(list)
for _ in range(m):
a, b = list(map(int, readline().split()))
if a == 1 or a == n:
if a not in d[b]:
d[b] += [a]
elif b == 1 or b == n:
if b not in d[a]:
d[a] += [b]
for k, v in list(d.items()):
if k != 1 and k != n:
if len(v) == 2:
print("POSSIBLE")
exit()
print("IMPOSSIBLE")
if __name__ == '__main__':
solve()
| p03645 |
def main():
n, m = list(map(int, input().split()))
root_start = []
root_goal = []
for i in range(m):
li = list(map(int, input().split()))
if li[0] == 1:
root_start.append(li[1])
elif li[1] == n:
root_goal.append(li[0])
flg = False
for ls in root_start:
if ls in root_goal:
flg = True
print('POSSIBLE') if flg else print('IMPOSSIBLE')
if __name__ == '__main__':
main()
| def main():
n, m = list(map(int, input().split()))
root_start = []
root_goal = []
ans = {}
for i in range(m):
li = list(map(int, input().split()))
if li[0] == 1:
ans.setdefault(li[1], 0)
ans[li[1]] += 1
elif li[1] == n:
ans.setdefault(li[0], 0)
ans[li[0]] += 1
flg = False
for k in ans:
if ans[k] >= 2:
flg = True
print('POSSIBLE') if flg else print('IMPOSSIBLE')
if __name__ == '__main__':
main()
| p03645 |
N, M = list(map(int, input().split()))
a = []
b = []
for i in range(M):
x, y = list(map(int, input().split()))
a.append(x)
b.append(y)
c = []
clear = 0
for i in range(M):
if b[i] == N:
c.append(a[i])
for i in range(M):
if a[i] == 1 and b[i] in c:
clear = 1
break
if clear == 1:
print('POSSIBLE')
else:
print('IMPOSSIBLE')
| N, M = list(map(int, input().split()))
a = []
b = []
for i in range(M):
x, y = list(map(int, input().split()))
a.append(x)
b.append(y)
c = []
d = []
for i in range(M):
if a[i] == 1:
c.append(b[i])
for i in range(M):
if b[i] == N:
d.append(a[i])
e = set(c) & set(d)
if len(e) != 0:
print('POSSIBLE')
else:
print('IMPOSSIBLE')
| p03645 |
N,M = list(map(int,input().split()))
x = 1
y = 1
for m in range(M):
a,b = list(map(int,input().split()))
if a==1:
x|=1<<b
if b==N:
y|=1<<a
print(("IM"*(x&y==1)+"POSSIBLE")) | N,M = list(map(int,input().split()))
x = set()
y = set()
for m in range(M):
a,b = list(map(int,input().split()))
if a==1:
x.add(b)
if b==N:
y.add(a)
if x&y:
print("POSSIBLE")
else:
print("IMPOSSIBLE") | p03645 |
N,M = list(map(int,input().split()))
S = [list(map(int,input().split())) for m in range(M)]
T = [s for s in S if 1 in s or N in s]
ans = "IMPOSSIBLE"
for n in range(1+N):
if [1,n] in T and [n,N] in T:
ans = "POSSIBLE"
print(ans) | N,M = list(map(int,input().split()))
x = set()
y = set()
for m in range(M):
a,b = list(map(int,input().split()))
if a==1:
x.add(b)
if b==N:
y.add(a)
if x&y:
print("POSSIBLE")
else:
print("IMPOSSIBLE") | p03645 |
N,M = list(map(int, input().split()))
mem = [[] for i in range(N)]
p1 = []
p2 = []
def solve():
for i in range(M):
a,b = list(map(int, input().split()))
if a == 1:
p1.append(b)
elif b == N:
p2.append(a)
for p in p1:
if p in p2: return True
return False
print(('POSSIBLE' if solve() else 'IMPOSSIBLE'))
| N,M = list(map(int, input().split()))
mem = [[] for i in range(N)]
p1 = []
p2 = []
def solve():
for i in range(M):
a,b = list(map(int, input().split()))
if a == 1:
p1.append(b)
elif b == N:
p2.append(a)
return len(set(p1) & set(p2)) > 0
print(('POSSIBLE' if solve() else 'IMPOSSIBLE'))
| p03645 |
N, M = list(map(int, input().split()))
ab = [tuple(map(int, input().split())) for _ in range(M)]
one_to_other = set([b for a, b in ab if a == 1])
other_to_n = set([a for a, b in ab if b == N])
way = one_to_other & other_to_n
if len(way) >= 1:
print("POSSIBLE")
else:
print("IMPOSSIBLE")
| N, M = list(map(int, input().split()))
first = set()
second = set()
for i in range(M):
a, b = list(map(int, input().split()))
if a == 1:
first.add(b)
if b == N:
second.add(a)
if first & second:
print("POSSIBLE")
else:
print("IMPOSSIBLE")
| p03645 |
# -*- coding: utf-8 -*-
"""
http://abc068.contest.atcoder.jp/tasks/arc079_a
"""
def solve(routes, N):
result = 'IMPOSSIBLE'
to_middle = set() # 島1から渡ることのできる島
from_middle = set() # 島Nへ渡ることのできる島
for f, t in routes:
if f == 1:
to_middle.add(t)
elif t == N:
from_middle.add(f)
if to_middle & from_middle:
result = 'POSSIBLE'
return result
def main():
N, M = list(map(int, input().split()))
routes = []
for _ in range(M):
routes.append([int(x) for x in input().split()])
result = solve(routes, N)
print(result)
if __name__ == '__main__':
main() | # -*- coding: utf-8 -*-
"""
http://abc068.contest.atcoder.jp/tasks/arc079_a
AC
"""
def solve(routes, N):
result = 'IMPOSSIBLE'
to_middle = set() # 島1から渡ることのできる島
from_middle = set() # 島Nへ渡ることのできる島
for f, t in routes:
if f == 1:
to_middle.add(t)
elif t == N:
from_middle.add(f)
if to_middle & from_middle:
result = 'POSSIBLE'
return result
def main():
N, M = list(map(int, input().split()))
routes = []
for _ in range(M):
routes.append([int(x) for x in input().split()])
result = solve(routes, N)
print(result)
if __name__ == '__main__':
# main()
to_middle = set() # 島1から渡ることのできる島
from_middle = set() # 島Nへ渡ることのできる島
N, M = list(map(int, input().split()))
for _ in range(M):
f, t = list(map(int, input().split()))
if f == 1:
to_middle.add(t)
elif t == N:
from_middle.add(f)
if to_middle & from_middle:
print('POSSIBLE')
else:
print('IMPOSSIBLE')
| p03645 |
to_middle = set() # 島1から渡ることのできる島
from_middle = set() # 島Nへ渡ることのできる島
N, M = list(map(int, (input().split())))
for _ in range(M):
f, t = list(map(int, (input().split())))
if f == 1:
to_middle.add(t)
elif t == N:
from_middle.add(f)
if to_middle & from_middle:
print('POSSIBLE')
else:
print('IMPOSSIBLE')
| from sys import stdin
input = stdin.readline
to_middle = set() # 島1から渡ることのできる島
from_middle = set() # 島Nへ渡ることのできる島
N, M = list(map(int, (input().split())))
for _ in range(M):
f, t = list(map(int, (input().split())))
if f == 1:
to_middle.add(t)
elif t == N:
from_middle.add(f)
if to_middle & from_middle:
print('POSSIBLE')
else:
print('IMPOSSIBLE')
| p03645 |
n,m = list(map(int,input().split()))
a_lst = []
for i in range(m):
a_lst.append( list(map(int,input().split())) )
ans = "IMPOSSIBLE"
start_lst = []
goal_lst = []
for a in a_lst:
if a[0] == 1:
start_lst.append(a[1])
if a[1] == n:
goal_lst.append(a[0])
for s in start_lst:
if s in goal_lst:
ans = "POSSIBLE"
print(ans) | n,m = list(map(int,input().split()))
start_set = set()
goal_set = set()
for i in range(m):
s,g = list(map(int,input().split()))
if s == 1:
start_set.add(g)
if g == n:
goal_set.add(s)
ans = "POSSIBLE" if (start_set & goal_set) else "IMPOSSIBLE"
print(ans) | p03645 |
n, m = list(map(int, input().split()))
first = []
second = []
for i in range(m):
a = list(map(int, input().split()))
if a[0] == 1:
first.append(a[1])
if a[1] == n:
second.append(a[0])
for i in first:
if i in second:
print('POSSIBLE')
exit()
print('IMPOSSIBLE') | n, m = list(map(int, input().split()))
first = []
second = []
for i in range(m):
a = list(map(int, input().split()))
if a[0] == 1:
first.append(a[1])
if a[1] == n:
second.append(a[0])
if len(set(first) & set(second)) > 0:
print('POSSIBLE')
else:
print('IMPOSSIBLE') | p03645 |
n, m = list(map(int, input().split()))
n -= 1
ab = [[] for i in range(n)]
for _ in range(m):
a, b = list(map(int, input().split()))
ab[a-1].append(b-1)
for i in ab[0]:
for j in ab[i]:
if j == n:
print("POSSIBLE")
exit()
print("IMPOSSIBLE") | n, m = list(map(int, input().split()))
x = [[] for _ in range(n)]
for _ in range(m):
a, b = list(map(int, input().split()))
x[a-1].append(b-1)
if x[0] == []:
print("IMPOSSIBLE")
exit()
for i in x[0]:
for j in x[i]:
if j == n-1:
print("POSSIBLE")
exit()
print("IMPOSSIBLE") | p03645 |
n, m = list(map(int, input().split()))
x = [[] for _ in range(n)]
for _ in range(m):
a, b = list(map(int, input().split()))
x[a-1].append(b-1)
if x[0] == []:
print("IMPOSSIBLE")
exit()
for i in x[0]:
for j in x[i]:
if j == n-1:
print("POSSIBLE")
exit()
print("IMPOSSIBLE") | n, m = list(map(int, input().split()))
x = [[] for _ in range(n)]
for _ in range(m):
a, b = list(map(int, input().split()))
x[a-1].append(b-1)
for i in x[0]:
for j in x[i]:
if j == n-1:
print("POSSIBLE")
exit()
print("IMPOSSIBLE") | p03645 |
n, m = list(map(int, input().split()))
AB = [tuple(map(int, input().split())) for _ in range(m)]
C = [b for a, b in AB if a == 1]
for a, b in AB:
if a in C and b == n:
print('POSSIBLE')
exit()
print('IMPOSSIBLE') | n, m = list(map(int, input().split()))
AB = [tuple(map(int, input().split())) for _ in range(m)]
C, D = set(), set()
for a, b in AB:
if a == 1:
C.add(b)
elif b == n:
D.add(a)
if len(C & D):
print('POSSIBLE')
else:
print('IMPOSSIBLE') | p03645 |
island, ship = list(map(int, input().split()))
startTo, fromGoal = [], []
for i in range(ship):
a, b = list(map(int, input().split()))
if a == 1:
startTo.append(b)
elif b == 1:
startTo.append(a)
elif a == island:
fromGoal.append(b)
elif b == island:
fromGoal.append(a)
check = False
if len(startTo) < len(fromGoal):
for i in range(len(startTo)):
check = startTo[i] in fromGoal
if check:
break
else:
for i in range(len(fromGoal)):
check = fromGoal[i] in startTo
if check:
break
if check:
print("POSSIBLE")
else:
print("IMPOSSIBLE") | island, ship = list(map(int, input().split()))
startTo, fromGoal = [False] * island, [False] * island
for i in range(ship):
a, b = list(map(int, input().split()))
if a == 1:
startTo[b - 1] = True
elif b == 1:
startTo[a - 1] = True
elif a == island:
fromGoal[b - 1] = True
elif b == island:
fromGoal[a - 1] = True
check = False
for i in range(island):
if startTo[i] and fromGoal[i]:
check = True
break
if check:
print("POSSIBLE")
else:
print("IMPOSSIBLE") | p03645 |
from collections import defaultdict
n,m=list(map(int,input().split()))
s=[tuple(map(int,input().split())) for _ in range(m)]
d=defaultdict(int)
for x in s:
d[x[0]]|=(1<<x[1])
d[x[1]]|=(1<<x[0])
if d[1]&d[n]>0:
print('POSSIBLE')
else:
print('IMPOSSIBLE')
| import sys
from collections import defaultdict
from heapq import heapify, heappush
n,m=list(map(int,input().split()))
s=[tuple(map(int,input().split())) for _ in range(m)]
def hl():
ret=[]
heapify(ret)
return ret
d=defaultdict(hl)
for x in s:
heappush(d[x[0]],-x[1])
heappush(d[x[1]],-x[0])
for e in d[1]:
if d[-e][0]==-n:
print('POSSIBLE')
sys.exit()
print('IMPOSSIBLE') | p03645 |
n, m = list(map(int, input().split()))
s = {tuple(map(int, input().split())) for _ in range(m)}
for i in range(2, n):
route = [1, i, n]
if all(edge in s for edge in zip(route, route[1:])):
print('POSSIBLE')
break
else:
print('IMPOSSIBLE')
| n, m = list(map(int, input().split()))
transit_a = set()
transit_b = set()
for _ in range(m):
a, b = list(map(int, input().split()))
if a == 1:
transit_b |= {b}
elif b == n:
transit_a |= {a}
print(('POSSIBLE' if len(transit_a & transit_b) else 'IMPOSSIBLE')) | p03645 |
n, m = list(map(int, input().split()))
transit_a = set()
transit_b = set()
for _ in range(m):
a, b = list(map(int, input().split()))
if a == 1:
transit_b |= {b}
elif b == n:
transit_a |= {a}
print(('POSSIBLE' if len(transit_a & transit_b) else 'IMPOSSIBLE')) | n, m = list(map(int, input().split()))
transit_a = set()
transit_b = set()
for _ in range(m):
a, b = list(map(int, input().split()))
if a == 1:
transit_b.add(b)
elif b == n:
transit_a.add(a)
print(('POSSIBLE' if len(transit_a & transit_b) else 'IMPOSSIBLE'))
| p03645 |
N,M = list(map(int,input().split()))
I = set()
n = set()
for i in range(M):
a,b = list(map(int,input().split()))
if a == 1:
I.add(b)
if b == 1:
I.add(a)
if a == N:
n.add(b)
if b == N:
n.add(a)
if I & n == set():
print("IMPOSSIBLE")
else:
print("POSSIBLE") | N,M = list(map(int,input().split()))
I = set()
n = set()
for i in range(M):
a,b = list(map(int,input().split()))
if a == 1:
I.add(b)
if b == N:
n.add(a)
if I & n == set():
print("IMPOSSIBLE")
else:
print("POSSIBLE") | p03645 |
n,m=list(map(int,input().split()))
A=[input().split() for _ in range(m)]
ans="IMPOSSIBLE"
for i in range(m):
if A[i][0]=="1":
if [A[i][1],str(n)] in A:
ans="POSSIBLE"
break
print(ans) | n,m=list(map(int,input().split()))
A=set()
B=set()
for i in range(m):
a,b=input().split()
if a=="1":
A.add(b)
if b==str(n):
B.add(a)
print(("POSSIBLE" if A&B else "IMPOSSIBLE")) | p03645 |
N, M = list(map(int, input().split()))
ab = [sorted(list(map(int, input().split()))) for _ in range(M)]
fst = []
scnd = []
for i in ab:
if i[0]==1:
fst.append(i[1])
if N in i:
scnd.append(i)
for i in scnd:
for j in fst:
if set(i) == set([j, N]):
print("POSSIBLE")
exit()
print("IMPOSSIBLE")
| N, M = list(map(int, input().split()))
ab = [sorted(list(map(int, input().split()))) for _ in range(M)]
fst = []
scnd = {}
for i in ab:
if i[0]==1:
fst.append(i[1])
if N in i:
idx = i.index(N)
scnd[i[1-idx]] = 0
#print(scnd,fst)
for j in fst:
if j in scnd:
print("POSSIBLE")
exit()
print("IMPOSSIBLE")
| p03645 |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.