Submission #101119

#	Time	Username	Problem	Language	Result	Execution time	Memory
101119		ae04071	Travelling Merchant (APIO17_merchant)	C++11	12 / 100	54 ms	3068 KiB

merchant

#include <bits/stdc++.h>
using namespace std;
using lli=long long;

int n,m,k;
lli adj[101][101], car[101][101], dist[100];
int s[100][1000],b[100][1000];

bool check(int C, bool f=false) {
    fill(dist, dist+n, 0);
    for(int t=0;t<n;t++) {
        int chg=0;
        for(int i=0;i<n;i++) for(int j=0;j<n;j++) if(adj[i][j]) {
            if(dist[j] > dist[i] + C*adj[i][j] - car[i][j]) {
                chg=1;
                dist[j] = dist[i] + C*adj[i][j] - car[i][j];
            }
        }
        if(!chg) break;
        if(t==n-1) return true;
    }
    if(f) {
        for(int i=0;i<n;i++)for(int j=0;j<n;j++) if(adj[i][j] && adj[j][i]){ 
            if(dist[i] + C*(adj[i][j]+adj[j][i]) - (car[i][j]+car[j][i]) == 0) return true;
        }
        return false;
    } else return false;
}
int main() {
    scanf("%d%d%d",&n,&m,&k);
    for(int i=0;i<n;i++) {
        for(int j=0;j<k;j++) scanf("%d%d",&b[i][j], &s[i][j]);
    }
    for(int i=0;i<m;i++) {
        int a,b;
        lli c;
        scanf("%d%d%lld",&a,&b,&c);
        a--;b--; adj[a][b] = c;
    }

    for(int k=0;k<n;k++) for(int i=0;i<n;i++) for(int j=0;j<n;j++) {
        if(adj[i][k] && adj[k][j] && (!adj[i][j] || adj[i][j] > adj[i][k]+adj[k][j])) {
            adj[i][j] = adj[i][k]+adj[k][j];
        }
    }
    
    for(int i=0;i<n;i++)for(int j=0;j<n;j++) if(adj[i][j]) {
        int ad=0;
        for(int t=0;t<k;t++) if(s[j][t]!=-1 && b[i][t]!=-1) {
            ad=max(ad,s[j][t]-b[i][t]);
        }
        car[i][j] = ad;
    }

    int lo=-1,up=1000000000;
    while(up-lo>1) {
        int md=(lo+up)>>1;
        if(check(md)) lo=md;
        else up=md;
    }
    if(check(lo+1, true)) lo++;
    printf("%d\n",lo);
    
    return 0;
}

Compilation message (stderr)

merchant.cpp: In function 'int main()':
merchant.cpp:30:10: 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:32:35: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         for(int j=0;j<k;j++) scanf("%d%d",&b[i][j], &s[i][j]);
                              ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~
merchant.cpp:37:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%d%d%lld",&a,&b,&c);
         ~~~~~^~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 12 / 12
• Subtask 2: 0 / 21
• Subtask 3: 0 / 33
• Subtask 4: 0 / 34