Submission #735241

#	Time	Username	Problem	Language	Result	Execution time	Memory
735241		Ronin13	Travelling Merchant (APIO17_merchant)	C++14	100 / 100	90 ms	5008 KiB

merchant

#include <bits/stdc++.h>
#define ll long long
#define f first
#define s second
#define pii pair<int,int>
#define pll pair<ll,ll>
#define pb push_back
#define epb emplace_back
#define ull unsigned ll
using namespace std;

const int nmax = 1001;

ll d[nmax][nmax];
ll g[nmax][nmax];
void floyd(int n){
    for(int k = 1; k <= n; k++){
        for(int j = 1; j <= n; j++){
            for(int i=  1; i <= n; ++i){
                d[i][j] = min(d[i][j], d[i][k] + d[k][j]);
            }
        }
    }
}

int32_t main(){
    ios_base::sync_with_stdio(false); cin.tie(0);
    int n; cin >> n;
    int m; cin >> m;
    int k; cin >> k;
    ll b[n + 1][k + 1], s[n + 1][k + 1];
    for(int i= 1; i <= n; i++){
        for(int j= 1; j <= k; j++){
            cin >> b[i][j] >> s[i][j];
        }
    }
    ll opt[n + 1][n + 1];
    for(int i= 1; i <= n; i++){
        for(int j = 1; j <= n; j++){
            opt[i][j] = -1e18;
            d[i][j] = 1e18;
            if(j == i) continue;
            opt[i][j] = 0;
            for(int x = 1; x <= k; x++){
                if(s[j][x] == -1 || b[i][x] == -1) continue;
                opt[i][j] = max(opt[i][j], s[j][x] - b[i][x]);
            }

        }
    }
    for(int i = 1; i <= m; i++){
        int u, v, t; cin >> u >> v >> t;
        d[u][v] = t;
    }
    floyd(n);
    for(int i= 1; i <= n; i++){
        for(int j = 1; j <= n; j++)
            g[i][j] = d[i][j];
    }

    ll l = 0, r = 1e9;
    int last = 0;
    while(l + 1 < r){

        ll mid = (l+ r) / 2;
        for(int i = 1; i <= n; i++){
            for(int j = 1; j <= n; j++)
                d[i][j] = 1e18;
        }
        for(int i = 1; i <= n; i++){
            for(int j = 1; j <= n; j++){
               // if(i == j) continue;
                d[i][j] = min(g[i][j], (ll)1e18 / mid) * mid - opt[i][j];
                d[i][j] = min(d[i][j], (ll)1e18);
              // d[i][i] = 0;
            }
        }

        floyd(n);

        bool good = false;
        for(int i = 1; i <= n; ++i)
            if(d[i][i] <= 0) good = true,last = i;
        if(good) l = mid;
        else r = mid;
    }
    cout << l;
    return 0;
}

Compilation message (stderr)

merchant.cpp: In function 'int32_t main()':
merchant.cpp:62:9: warning: variable 'last' set but not used [-Wunused-but-set-variable]
   62 |     int last = 0;
      |         ^~~~

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