UVA 1329

带权值的并查集的应用；

代码：

#include<cstdio>
#include<algorithm>
#include<cmath>
#include<cstring>
#define maxn 20005
using namespace std;

int f[maxn];
int d[maxn];
int t,n,x,y;
char s[5];

int find(int x)
{
    if(f[x]!=x)
    {
        int r=find(f[x]);
        d[x]+=d[f[x]];
        return f[x]=r;
    }
    else return x;
}

int main()
{
    scanf("%d",&t);
    while(t--)
    {
        scanf("%d",&n);
        for(int i=1; i<=n; i++){f[i]=i;d[i]=0;}
        while(scanf("%s",s))
        {
            if(s[0]=='O')break;
            if(s[0]=='E')
            {
                scanf("%d",&x);
                find(x);
                printf("%d
",d[x]);
            }
            else if(s[0]=='I')
            {
                scanf("%d%d",&x,&y);
                f[x]=y;
                d[x]=abs(x-y)%1000;
            }
        }
    }
    return 0;
}