hdu 1217(Floyd 演算法)

自己還是比較容易受外界影響，外面一有什麼風吹草動，就沒心思繼續做題了，該死，就不能集中下精神  啊，

#include <iostream>#include<cstdio>#include<string.h>using namespace std;double a[35][35];char s[35][100],s1[35],s2[35];int n;bool flag;void Floyd(){for(int k=0;k<n;k++)for(int i=0;i<n;i++)for(int j=0;j<n;j++){if(a[i][j]<a[i][k]*a[k][j])//此處加變乘，小於變大於a[i][j]=a[i][k]*a[k][j];}int i;for(i=0;i<n;i++)if(a[i][i]>1){flag=true;break;}if(i==n)flag=false;}int main(){int m,count=1;double c;while(scanf("%d",&n)&&n){for(int i=0;i<n;i++)scanf("%s",s[i]);memset(a,0,sizeof(a));scanf("%d",&m);while(m--){int i,j;scanf("%s%lf%s",s1,&c,s2);for(i=0;i<n;i++)if(strcmp(s1,s[i])==0)break;for(j=0;j<n;j++)if(strcmp(s2,s[j])==0)break;a[i][j]=c;}printf("Case %d: ",count++);Floyd();if(flag)puts("Yes");elseputs("No");}}