Shared code

#include <bits/stdc++.h>
#define pb push_back
using namespace std;

const int64_t INF = LLONG_MAX-1;
const int N = 500+10;
vector<vector<int64_t>> dist(N , vector<int64_t>(N , INF));

int64_t n,m,q;

void floydWarshall(){
    int i, j, k;
    for (k = 0; k <= n; k++) {
        for (i = 0; i <= n; i++) {
            for (j = 0; j <= n; j++) {
                if (dist[i][j] > (dist[i][k] + dist[k][j]) && (dist[k][j] != INF && dist[i][k] != INF))
                    dist[i][j] = dist[i][k] + dist[k][j];
            }
        }
    }
}

int main(){
    cin.tie(0)->ios::sync_with_stdio(0);
    cin>>n>>m>>q;
    for(int64_t i=0;i<m;i++){
        int64_t a,b,c;
        cin>>a>>b>>c;
        dist[a][b]=min(dist[a][b], c);
        dist[b][a]=min(dist[b][a], c);
    }
    floydWarshall();
    for(int64_t i=0;i<q;i++){
        int64_t a,b;
        cin>>a>>b;
        if(a==b){
            cout<<0<<'\n';
        }else
            cout<<((min(dist[b][a],dist[a][b])==INF)?-1:dist[a][b])<<'\n';
    }
}