Submission #367989

#	Time	Username	Problem	Language	Result	Execution time	Memory
367989		parsabahrami	Travelling Merchant (APIO17_merchant)	C++17	100 / 100	219 ms	3564 KiB

merchant

// Call my Name and Save me from The Dark
#include <bits/stdc++.h>
 
using namespace std;

typedef long long int ll;
typedef pair<int, int> pii;
 
#define SZ(x)                       (int) x.size()
#define F                           first
#define S                           second

const int N = 110, M = 9905, K = 1e3 + 10;
int n, m, k, w[M], from[M], to[M], S[N][K], B[N][K]; ll dp[N][N], C[N][N];

void Fill() {
    for (int i = 1; i <= n; i++) {
        for (int j = 1; j <= n; j++) {
            dp[i][j] = -1e18;
            if (i == j) dp[i][j] = 0;
        }
    }
}

int check(ll x) {
    Fill();
    for (int i = 1; i <= m; i++) {
        int u = from[i], v = to[i];
        dp[u][v] = max(dp[u][v], -w[i] * x);
    }
    for (int p = 1; p <= n; p++) 
        for (int i = 1; i <= n; i++) 
            for (int j = 1; j <= n; j++) dp[i][j] = min((ll) 1e18, max(dp[i][j], dp[i][p] + dp[p][j]));
    for (int i = 1; i <= n; i++) 
        for (int j = 1; j <= n; j++) dp[i][j] += C[i][j];
    for (int p = 1; p <= n; p++) 
        for (int i = 1; i <= n; i++) 
            for (int j = 1; j <= n; j++) dp[i][j] = min((ll) 1e18, max(dp[i][j], dp[i][p] + dp[p][j]));
    for (int i = 1; i <= n; i++) 
        for (int j = 1; j <= n; j++) 
            if (i != j && dp[i][j] + dp[j][i] >= 0) return 1;
    return 0;
}

int main() {
    scanf("%d%d%d", &n, &m, &k);
    for (int i = 1; i <= n; i++) {
        for (int j = 1; j <= k; j++) scanf("%d%d", &B[i][j], &S[i][j]);
    }
    for (int i = 1; i <= m; i++) {
        scanf("%d%d%d", &from[i], &to[i], &w[i]);
    }
    for (int u = 1; u <= n; u++) {
        for (int v = 1; v <= n; v++) {
            for (int i = 1; i <= k; i++) 
                if (~B[u][i] && ~S[v][i]) C[u][v] = max(C[u][v], (ll) S[v][i] - B[u][i]);
        }
    }
    ll l = 0, r = 1e9;
    while (r - l > 1) {
        ll mid = (l + r) >> 1;
        if (check(mid)) l = mid;
        else r = mid;
    }
    printf("%lld\n", l);
    return 0;
}

Compilation message (stderr)

merchant.cpp: In function 'int main()':
merchant.cpp:46:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   46 |     scanf("%d%d%d", &n, &m, &k);
      |     ~~~~~^~~~~~~~~~~~~~~~~~~~~~
merchant.cpp:48:43: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   48 |         for (int j = 1; j <= k; j++) scanf("%d%d", &B[i][j], &S[i][j]);
      |                                      ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~
merchant.cpp:51:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   51 |         scanf("%d%d%d", &from[i], &to[i], &w[i]);
      |         ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

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