Submission #1692294

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Source Code Expand

#include<iostream>
#include<algorithm>
#include<cstdio>
#include<cmath>
#include<math.h>
#include<string>
#include<string.h>
#include<stack>
#include<queue>
#include<vector>
#include<utility>
#include<set>
#include<map>
#include<stdlib.h>
#include<iomanip>

using namespace std;

#define ll long long
#define ld long double
#define EPS 0.0000000001
#define INF 1e9
#define MOD 1000000007
#define rep(i,n) for(i=0;i<n;i++)
#define loop(i,a,n) for(i=a;i<n;i++)
#define all(in) in.begin(),in.end()
#define shosu(x) fixed<<setprecision(x)

typedef vector<int> vi;
typedef pair<int,int> pii;

int main(void) {
  int i,j,k,l;
  int t;
  cin>>t;
  rep(l,t){
    int n;
    cin>>n;
    vector<vi> dp(n,vi(n));
    rep(i,n)rep(j,n)cin>>dp[i][j];
    rep(i,n)rep(j,n)if(dp[i][j]==-1)dp[i][j]=INF;
    bool ans=true;
    rep(k,n)rep(i,n)rep(j,n)
      if(dp[i][j]>dp[i][k]+dp[k][j])ans=false;
      else if(i==j&&dp[i][j])ans=false;
    if(ans)cout<<"YES"<<endl;
    else cout<<"NO"<<endl;
  }
}

Submission Info

Judge Result