Description
Input
Output
Sample Input
3 Alice Bob Smith John Alice Smith 5 a c c d d e b e a d 0
Sample Output
Yes No
#include<stdio.h>
#include<string.h>
int main()
{
int n,i,j,m,c[1010],o;
char a[1010][101],b[1010][101],d[1010][101];
while(scanf("%d%*c",&n),n!=0)
{
o=m=0;
memset(c,0,sizeof(c));
for(i=0;i<n;i++)
{
scanf("%s %s",a[i],b[i]);
}
for(j=0;j<n;j++)
for(i=0;i<n;i++)
if(strcmp(a[j],b[i])==0)c[j]++;
for(i=0;i<n;i++)
if(c[i]==0){strcpy(d[o++],a[i]);}
if(o>=1)for(i=0;i<o-1;i++)
if(strcmp(d[i],d[i+1])!=0)break;
if(i==o-1&&o>=1)printf("Yes\n");
else printf("No\n");
}
}原文：http://blog.csdn.net/yuanhanchun/article/details/19823349