http://poj.org/problem?id=3318
g++ re c++ ac
Unbearable
Random looking for a 60000-point comparison of good luck on the past
#include<iostream>
#include<cstdio>
#include<cstdlib>
#include<ctime>
#include<queue>
#include<cstring>
#include<set>
#include<cmath>
#include<algorithm>
using namespace std;
const int N=505;
int a[N][N];
int b[N][N];
int c[N][N];
int main()
{
//freopen("data.txt","r",stdin);
int n;
scanf("%d",&n);
for(int i=0;i<n;++i)
for(int j=0;j<n;++j)
scanf("%d",&a[i][j]);
for(int i=0;i<n;++i)
for(int j=0;j<n;++j)
scanf("%d",&b[i][j]);
for(int i=0;i<n;++i)
for(int j=0;j<n;++j)
scanf("%d",&c[i][j]);
srand((unsigned int)time(NULL));
int I=60000;
bool flag=true;
while(I--)
{
int k=rand()%n;
int l=rand()%n;
int temp=0;
for(int i=0;i<n;++i)
{
temp+=(a[k][i]*b[i][l]);
}
if(temp!=c[k][l])
{
flag=false;
break;
}
}
if(flag==true)
printf("YES\n");
else
printf("NO\n");
return 0;
}
Reproduced in: https: //www.cnblogs.com/liulangye/archive/2012/07/30/2615182.html