6135 Cow Hurdles

https://www.acmicpc.net/problem/6135

#include <cstdio>
#include <algorithm>
#define INF 987654321
using namespace std;
 
int n,m,t,u,v,w,i,j,k,d[301][301];
 
int main()
{
    scanf("%d %d %d",&n,&m,&t);
    for(i=1;i<=n;i++) for(j=1;j<=n;j++) d[i][j]=i==j?0:INF;
    while(m--) scanf("%d %d %d",&u,&v,&w),d[u][v]=w;
    for(k=1;k<=n;k++) for(i=1;i<=n;i++) for(j=1;j<=n;j++)
        d[i][j]=min(d[i][j],max(d[i][k],d[k][j]));
    while(t--) scanf("%d %d",&u,&v),printf("%d\n",d[u][v]==INF?-1:d[u][v]);
    return 0;
}