經典的並查集,最後確認兩個數是不是親戚的時候要兩個數都要再找一次祖先,一樣的就yes,不一樣就no
#include <stdio.h>
#define maxn 5000int father[maxn] ;
int find (int x)
{
if(x!=father[x])father[x]=find(father[x]);
return father[x];
}
int lianjie(int x,int y)
{
int rx,ry;
rx=find(x);
ry=find(y);
if(rx!=ry)
{
father[ry]=rx;
}
}
int main(int argc, char *argv[])
{
int x,y;
int n,m,p;
int i,j,flag=0;
for(i=1;i<maxn;++i)
father[i]=i;
scanf("%d%d%d",&n,&m,&p);
for(i=0;i<m;i++)
{
scanf("%d%d",&x,&y);
lianjie(x,y);
}
for(i=0;i<p;i++)
{
scanf("%d%d",&x,&y);
x=find(x);
y=find(y);
if(x==y)printf("Yes\n");
else printf("No\n");
}
return 0;
}