LA 3027 - Corporative Network

#include <cstdio>
#include <algorithm>
#include <cstring>
using namespace std;
const int Tmax=20005;
int n,pa[Tmax],dist[Tmax];
int find(int x)
{
if(pa[x]==x) return x;
int root=find(pa[x]);
dist[x]+=dist[pa[x]];
return pa[x]=root;
}
int main()
{
int i,T,a,b,fa;
char ch;
scanf("%d",&T);
while(T--){
scanf("%d",&n);
for(i=1;i<=n;i++)
pa[i]=i;
memset(dist,0,sizeof(dist));
getchar();
while(scanf("%c",&ch)==1&&ch!='O'){
if(ch=='I'){
scanf("%d %d",&a,&b);
dist[a]=abs(b-a)%1000;
fa=find(a);
pa[fa]=b;
}
else {
scanf("%d",&a);
find(a);
printf("%d\n",dist[a]);
}
getchar();
}
}
return 0;
}