Submission #161840

#	Time	Username	Problem	Language	Result	Execution time	Memory
161840		Minnakhmetov	Travelling Merchant (APIO17_merchant)	C++14	100 / 100	229 ms	5496 KiB

merchant

#include <bits/stdc++.h>
    
#define ll long long
#define all(aaa) aaa.begin(), aaa.end()
 
using namespace std;

const ll INF = 1e18;
const int N = 1005;
ll prof[N][N], dp[N][N], 
    b[N][N], s[N][N], w[N][N];

signed main() {
    ios_base::sync_with_stdio(0);
    cin.tie(NULL);

    int n, m, k;
    cin >> n >> m >> k;

    for (int i = 0; i < n; i++) {
        for (int j = 0; j < n; j++) {
            w[i][j] = INF;
        }
    }

    for (int i = 0; i < n; i++) {
        for (int j = 0; j < k; j++) {
            cin >> b[i][j] >> s[i][j];
        }
    }

    for (int i = 0; i < m; i++) {
        ll a, b, c;
        cin >> a >> b >> c;
        a--, b--;
        w[a][b] = min(w[a][b], c);
    }

    for (int i = 0; i < n; i++) {
        for (int j = 0; j < n; j++) {
            for (int k = 0; k < n; k++) {
                if (w[j][i] != INF && w[i][k] != INF) {
                    w[j][k] = min(w[j][k], w[j][i] + w[i][k]);
                }
            }
        }
    }

    for (int x = 0; x < n; x++) {
        for (int y = 0; y < n; y++) {
            for (int z = 0; z < k; z++) {
                if (b[x][z] != -1 && s[y][z] != -1) {
                    prof[x][y] = max(prof[x][y], s[y][z] - b[x][z]); 
                }
            }
        }
    }

    ll l = 0, r = 3e9;

    while (r - l > 1) {
        ll p = (l + r) >> 1;

        for (int i = 0; i < n; i++) {
            for (int j = 0; j < n; j++) {
                if (w[i][j] != INF) {
                    dp[i][j] = prof[i][j] - w[i][j] * p;
                }
            }
        }

        bool ok = false;

        for (int x = 0; x < n; x++) {
            for (int y = 0; y < n; y++) {
                for (int z = 0; z < n; z++) {
                    if (w[y][x] != INF && w[x][z] != INF) {
                        dp[y][z] = max(dp[y][z], dp[y][x] + dp[x][z]);

                        if (y == z && dp[y][z] >= 0) {
                            ok = true;
                        }
                    }
                }
            }
        }

        if (ok) {
            l = p;
        }
        else {
            r = p;
        }
    }

    cout << l;

    return 0;
}

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