File size: 6,351 Bytes
14c9c2b | 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 | #include <iostream>
#include <vector>
#include <string>
#include <algorithm>
#include <map>
#include <ctime>
#include <cstdlib>
using namespace std;
// Structure to represent each treasure category
struct Item {
string name;
int id;
long long q; // quantity
long long v; // value
long long m; // mass
long long l; // volume
};
// Global capacity constraints
const long long MAX_M = 20000000; // 20 kg in mg
const long long MAX_L = 25000000; // 25 L in uL
// Structure to represent a solution state
struct Solution {
vector<int> counts;
long long total_v;
long long total_m;
long long total_l;
Solution(int n) : counts(n, 0), total_v(0), total_m(0), total_l(0) {}
};
vector<Item> items;
int N;
// Parse the JSON-like input
void parseInput() {
string input, line;
// Read all stdin into a single string
while (getline(cin, line)) {
input += line + " ";
}
vector<string> tokens;
string current;
bool inQuotes = false;
for (char c : input) {
if (inQuotes) {
if (c == '"') {
inQuotes = false;
if (!current.empty()) tokens.push_back(current);
current = "";
} else {
current += c;
}
} else {
if (c == '"') {
inQuotes = true;
} else if (isdigit(c) || c == '-') {
current += c;
} else {
if (!current.empty()) {
tokens.push_back(current);
current = "";
}
}
}
}
if (!current.empty()) tokens.push_back(current);
// Tokens are expected in groups of 5: Key, q, v, m, l
for (size_t i = 0; i < tokens.size(); i += 5) {
if (i + 4 >= tokens.size()) break;
Item item;
item.name = tokens[i];
item.id = (int)items.size();
item.q = stoll(tokens[i+1]);
item.v = stoll(tokens[i+2]);
item.m = stoll(tokens[i+3]);
item.l = stoll(tokens[i+4]);
items.push_back(item);
}
N = (int)items.size();
}
// Greedily fill the bag based on a specific item order
void fillGreedy(Solution& sol, const vector<int>& order) {
for (int idx : order) {
if (sol.counts[idx] >= items[idx].q) continue;
long long rem_m = MAX_M - sol.total_m;
long long rem_l = MAX_L - sol.total_l;
if (rem_m < items[idx].m || rem_l < items[idx].l) continue;
long long take_m = rem_m / items[idx].m;
long long take_l = rem_l / items[idx].l;
long long take_q = items[idx].q - sol.counts[idx];
long long count = min({take_m, take_l, take_q});
if (count > 0) {
sol.counts[idx] += count;
sol.total_v += count * items[idx].v;
sol.total_m += count * items[idx].m;
sol.total_l += count * items[idx].l;
}
}
}
int main() {
ios_base::sync_with_stdio(false);
cin.tie(NULL);
srand((unsigned)time(NULL));
parseInput();
if (N == 0) {
cout << "{}" << endl;
return 0;
}
double start_time = (double)clock() / CLOCKS_PER_SEC;
Solution bestSol(N);
int iterations = 0;
// Keep trying to improve the solution until time limit approaches
while (true) {
iterations++;
// Check time every 50 iterations to avoid overhead
if (iterations % 50 == 0) {
double curr_time = (double)clock() / CLOCKS_PER_SEC;
if (curr_time - start_time > 0.95) break;
}
// Generate a random tradeoff parameter alpha between mass and volume
double alpha = (double)rand() / RAND_MAX;
// Ensure we test pure Mass and pure Volume heuristics occasionally
if (iterations == 1) alpha = 0.0;
else if (iterations == 2) alpha = 1.0;
else if (iterations == 3) alpha = 0.5;
// Calculate score for each item based on value per weighted resource usage
vector<pair<double, int>> density(N);
for (int i = 0; i < N; ++i) {
// Normalize costs to capacity to make alpha meaningful
double w_m = (double)items[i].m / MAX_M;
double w_l = (double)items[i].l / MAX_L;
double cost = alpha * w_m + (1.0 - alpha) * w_l;
if (cost < 1e-15) cost = 1e-15;
density[i] = { (double)items[i].v / cost, i };
}
// Sort items by calculated density
sort(density.rbegin(), density.rend());
vector<int> order;
for(auto p : density) order.push_back(p.second);
// Construct initial greedy solution
Solution currSol(N);
fillGreedy(currSol, order);
// Local Search: "Remove-1-and-Fill" Strategy
// Try to escape local optima by removing one item and refilling greedily
bool improved = true;
while (improved) {
improved = false;
Solution localBest = currSol;
for (int i = 0; i < N; ++i) {
if (currSol.counts[i] > 0) {
Solution temp = currSol;
// Remove 1 unit of item i
temp.counts[i]--;
temp.total_v -= items[i].v;
temp.total_m -= items[i].m;
temp.total_l -= items[i].l;
// Try to fill remaining space
fillGreedy(temp, order);
if (temp.total_v > localBest.total_v) {
localBest = temp;
improved = true;
}
}
}
if (improved) currSol = localBest;
}
if (currSol.total_v > bestSol.total_v) {
bestSol = currSol;
}
}
// Output result in JSON format
cout << "{";
map<string, int> outMap;
for(int i=0; i<N; ++i) {
outMap[items[i].name] = bestSol.counts[i];
}
bool first = true;
for (auto const& [key, val] : outMap) {
if (!first) cout << ",";
cout << "\n \"" << key << "\": " << val;
first = false;
}
cout << "\n}" << endl;
return 0;
} |