Submission #589347

#	Time	Username	Problem	Language	Result	Execution time	Memory
589347		stevancv	Travelling Merchant (APIO17_merchant)	C++14	100 / 100	74 ms	3412 KiB

merchant

#include <bits/stdc++.h>
#define ll long long
#define ld long double
#define sp ' '
#define en '\n'
#define smin(a, b) a = min(a, b)
#define smax(a, b) a = max(a, b)
using namespace std;
int main() {
    ios::sync_with_stdio(false);
    cin.tie(0);
    cout.tie(0);
    int n, m, k;
    cin >> n >> m >> k;
    vector<vector<int>> a(n, vector<int>(2 * k));
    for (int i = 0; i < n; i++) {
        for (int j = 0; j < 2 * k; j++) {
            cin >> a[i][j];
        }
    }
    vector<vector<ll>> dist(n, vector<ll>(n, 1e18));
    for (int i = 0; i < m; i++) {
        int x, y, z; cin >> x >> y >> z;
        x -= 1; y -= 1;
        dist[x][y] = z;
    }
    for (int l = 0; l < n; l++) {
        for (int i = 0; i < n; i++) {
            for (int j = 0; j < n; j++) {
                smin(dist[i][j], dist[i][l] + dist[l][j]);
            }
        }
    }
    vector<vector<ll>> opt(n, vector<ll>(n));
    for (int i = 0; i < n; i++) {
        for (int j = 0; j < n; j++) {
            ll x = 0;
            for (int l = 0; l < k; l++) {
                if (a[i][2 * l] == -1 || a[j][2 * l + 1] == -1) continue;
                ll tx = a[j][2 * l + 1] - a[i][2 * l];
                smax(x, tx);
            }
            opt[i][j] = x;
        }
    }
    auto Can = [&] (ll x) {
        vector<vector<ll>> d(n, vector<ll>(n, 1e18));
        for (int i = 0; i < n; i++) for (int j = 0; j < n; j++) d[i][j] = x * min(dist[i][j], (ll)1e18 / x) - opt[i][j];
        for (int o = 0; o < n; o++) for (int i = 0; i < n; i++) for (int j = 0; j < n; j++) smin(d[i][j], d[i][o] + d[o][j]);
        for (int i = 0; i < n; i++) if (d[i][i] <= 0) return true;
        return false;
    };
    ll l = 1; ll r = 1e9;
    ll ans = 0;
    while (l <= r) {
        ll mid = l + r >> 1;
        if (Can(mid)) {
            ans = mid;
            l = mid + 1;
        }
        else r = mid - 1;
    }
    cout << ans << en;
    return 0;
}

Compilation message (stderr)

merchant.cpp: In function 'int main()':
merchant.cpp:56:20: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   56 |         ll mid = l + r >> 1;
      |                  ~~^~~

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