POJ 1703 Find them, Catch them(种类并查集)

题目链接

这种类型的题目以前见过，今天第一次写，具体过程，还要慢慢理解。

 #include <cstring>
 #include <cstdio>
 #include <string>
 #include <iostream>
 #include <algorithm>
 #include <vector>
 using namespace std;
 int o[];
 int flag[];
 int find(int x)
 {
     if (x == o[x]) return x;
     int t = find(o[x]);
     flag[x] = (flag[o[x]] + flag[x]) % ;
     return o[x] = t;
 }
 void merge(int x,int y)
 {
     int tx,ty;
     tx = find(x);
     ty = find(y);
     if(tx != ty)
     {
         o[tx] = ty;
         flag[tx] = (flag[x]+flag[y]+)%;
     }
 }
 int judge(int x,int y)
 {
     int tx,ty;
     tx = find(x);
     ty = find(y);
     if(tx != ty)
     return -;
     else
     return (flag[x] == flag[y]);
 }
 int main()
 {
     int T,sv,ev,i,n,m;
     char ch;
     scanf("%d",&T);
     while(T--)
     {
         scanf("%d%d%*c",&n,&m);
         for(i = ;i <= n;i ++)
         {
             flag[i] = ;
             o[i] = i;
         }
         for(i = ;i < m;i ++)
         {
             scanf("%c%*c%d%d%*c",&ch,&sv,&ev);
             if(ch == 'A')
             {
                 int temp = judge(sv,ev);
                 if(temp == -)
                 printf("Not sure yet.\n");
                 else if(temp == )
                 printf("In different gangs.\n");
                 else
                 printf("In the same gang.\n");
             }
             else
             {
                 merge(sv,ev);
             }
         }
     }
     return ;
 }