Submission #165450

#	Time	Username	Problem	Language	Result	Execution time	Memory
165450		fedoseevtimofey	Travelling Merchant (APIO17_merchant)	C++14	100 / 100	130 ms	3456 KiB

merchant

#include <bits/stdc++.h>
 
using namespace std;
typedef long long ll;
 
const int Inf = 1e9;
 
int main() {
  ios_base::sync_with_stdio(false); cin.tie(0);
#ifdef LOCAL
  freopen("input.txt", "r", stdin);
#endif 
  int n, m, k;
  cin >> n >> m >> k;
  vector <vector <int>> s(n, vector <int> (k)), b(n, vector <int> (k));
  for (int i = 0; i < n; ++i) {
    for (int j = 0; j < k; ++j) {
      cin >> b[i][j] >> s[i][j];
    }
  }
  vector <vector <int>> d(n, vector <int> (n, Inf));
  for (int i = 0; i < m; ++i) {
    int u, v, x;
    cin >> u >> v >> x;
    --u, --v;
    d[u][v] = x;
  }
  for (int k = 0; k < n; ++k) {
    for (int i = 0; i < n; ++i) {
      for (int j = 0; j < n; ++j) {
        d[i][j] = min(d[i][j], d[i][k] + d[k][j]);
      }
    }
  }
  vector <vector <int>> best(n, vector <int> (n, 0));
  for (int i = 0; i < n; ++i) {
    for (int j = 0; j < n; ++j) {
      for (int id = 0; id < k; ++id) {
        if (s[j][id] != -1 && b[i][id] != -1) best[i][j] = max(best[i][j], s[j][id] - b[i][id]);
      }
    }
  }
  vector <vector <ll>> w(n, vector <ll> (n));
  int l = 0, r = 1e9 + 7;
  while (r - l > 1) {
    int m = (l + r) >> 1;
    for (int i = 0; i < n; ++i) {
      for (int j = 0; j < n; ++j) {
        w[i][j] = best[i][j] - (ll)m * d[i][j];
      }
    }
    for (int k = 0; k < n; ++k) {
      for (int i = 0; i < n; ++i) {
        for (int j = 0; j < n; ++j) {
          w[i][j] = max(w[i][j], w[i][k] + w[k][j]);
        }
      }
    }
    bool fl = false;
    for (int i = 0; i < n; ++i) {
      if (w[i][i] >= 0) fl = true;
    }
    if (fl) l = m;
    else r = m;
  }
  cout << l << '\n';
}

• Subtask 1: 12 / 12
• Subtask 2: 21 / 21
• Subtask 3: 33 / 33
• Subtask 4: 34 / 34