HDU 1596 find the safest road

用floyd水之，注意格式问题

#include<stdio.h>#include<string.h>#include<algorithm>using namespace std;#define N 1005double w[N][N];int main(){    int n;    while(scanf("%d",&n)!=EOF)    {        int i,j,k;        double v;        for(i=1; i<=n; i++)        {            for(j=1; j<=n; j++)            {                scanf("%lf",&v);                w[i][j]=v;            }        }        for(k=1;k<=n;k++)        {            for(i=1;i<=n;i++)            {                for(j=1;j<=n;j++)                {                    w[i][j]=max(w[i][j],w[i][k]*w[k][j]);                }            }        }        int r,a,b;        scanf("%d",&r);        for(i=0;i<r;i++)        {            scanf("%d%d",&a,&b);            if(!w[a][b])            {                printf("What a pity!\n");            }            else            {                printf("%0.3lf\n",w[a][b]);            }        }    }    return 0;}