Submission #59365

#	Time	Username	Problem	Language	Result	Execution time	Memory
59365		duality	Travelling Merchant (APIO17_merchant)	C++11	100 / 100	121 ms	9796 KiB

merchant

#include <bits/stdc++.h>
using namespace std;
#define pb push_back
#define mp make_pair
typedef long long int LLI;
typedef pair<int,int> pii;
typedef vector<int> vi;
typedef vector<pii> vpii;

int B[100][1000],S[100][1000];
int dist[100][100],profit[100][100];
LLI dist2[100][100];
int main() {
    int i,j;
    int N,M,K;
    int u,v,t;
    scanf("%d %d %d",&N,&M,&K);
    for (i = 0; i < N; i++) {
        for (j = 0; j < K; j++) scanf("%d %d",&B[i][j],&S[i][j]);
    }
    for (i = 0; i < N; i++) fill(dist[i],dist[i]+N,1e9);
    for (i = 0; i < M; i++) {
        scanf("%d %d %d",&u,&v,&t);
        u--,v--;
        dist[u][v] = min(dist[u][v],t);
    }

    int k;
    for (k = 0; k < N; k++) {
        for (i = 0; i < N; i++) {
            for (j = 0; j < N; j++) dist[i][j] = min(dist[i][j],dist[i][k]+dist[k][j]);
        }
    }
    for (i = 0; i < N; i++) {
        for (j = 0; j < N; j++) {
            int m = 0;
            for (k = 0; k < K; k++) {
                if ((B[i][k] != -1) && (S[j][k] != -1)) m = max(m,S[j][k]-B[i][k]);
            }
            profit[i][j] = m;
        }
    }
    LLI l = 0,r = 1e9;
    while (l < r) {
        LLI m = (l+r+1) / 2;

        for (i = 0; i < N; i++) {
            for (j = 0; j < N; j++) dist2[i][j] = profit[i][j]-m*dist[i][j];
        }
        for (k = 0; k < N; k++) {
            for (i = 0; i < N; i++) {
                for (j = 0; j < N; j++) dist2[i][j] = max(dist2[i][j],dist2[i][k]+dist2[k][j]);
            }
        }
        for (i = 0; i < N; i++) {
            if (dist2[i][i] >= 0) break;
        }
        if (i < N) l = m;
        else r = m-1;
    }
    printf("%lld\n",l);

    return 0;
}

Compilation message (stderr)

merchant.cpp: In function 'int main()':
merchant.cpp:17:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d %d %d",&N,&M,&K);
     ~~~~~^~~~~~~~~~~~~~~~~~~~~
merchant.cpp:19:38: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         for (j = 0; j < K; j++) scanf("%d %d",&B[i][j],&S[i][j]);
                                 ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~
merchant.cpp:23:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%d %d %d",&u,&v,&t);
         ~~~~~^~~~~~~~~~~~~~~~~~~~~

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