POJ 1703 Find them,Catch them ----种类并查集(经典)

#include <iostream>
#include <cstdio>
#include <cstring>
#include <cmath>
#include <algorithm>
using namespace std;
#define N 100100

int fa
,same
;

void makeset(int n)
{
for(int i=1;i<=n;i++)
{
fa[i] = i;
same[i] = 0;
}
}

int findset(int x)
{
if(x != fa[x])
{
int tmp = fa[x];
fa[x] = findset(fa[x]);
same[x] = (same[x] + same[tmp])%2;
}
return fa[x];
}

int unionset(char s,int a,int b)
{
int x = findset(a);
int y = findset(b);
if(x == y)    //属于同一个集合
{
if(s == 'A')
{
if(same[a] == same[b])
{
return 1;  //same
}
else
{
return 0;  //different
}
}
}
else  //不属于同一个集合
{
if(s == 'A')
{
return 2;    //unsure
}
else if(s == 'D')
{
fa[x] = y;
same[x] = (same[a] + same[b] + 1)%2;
}
}
return 3;  //要加，这是对其他情况的处理，因为此函数必须返回一个值
}

int main()
{
int t,n,m,i;
char ss[5];
int a,b;
scanf("%d",&t);
while(t--)
{
scanf("%d%d",&n,&m);
makeset(n);
for(i=0;i<m;i++)
{
scanf("%s %d %d",ss,&a,&b);
if(unionset(ss[0],a,b) == 1)
{
cout<<"In the same gang."<<endl;
}
else if(unionset(ss[0],a,b) == 0)
{
cout<<"In different gangs."<<endl;
}
else if(unionset(ss[0],a,b) == 2)
{
cout<<"Not sure yet."<<endl;
}
}
}
return 0;
}