HDU1213

并查集超级水题

#include<iostream>#include<queue>#include<stack>#include<cstdlib>#include<memory.h>using namespace std;int map[1001];int book[1001];int gen(int x){    while(x!=map[x])    {        x=map[x];    }    return x;}void hebing(int a,int b){    int a1=gen(a);    int b1=gen(b);    if(a1!=b1)    {        map[a1]=b1;    }}int main(){    int T;    cin>>T;    while(T--)    {        memset(book,0,sizeof(book));        int n,m;        cin>>n>>m;        for(int a=1;a<=n;a++)map[a]=a;        for(int sd=1;sd<=m;sd++)        {            int s,d;            cin>>s>>d;            hebing(s,d);        }        for(int a=1;a<=n;a++)        {            book[gen(a)]=1;        }        int sum=0;        for(int a=1;a<=n;a++)        {            if(book[a]==1)sum++;        }        cout<<sum<<endl;    }    return 0;}