开三倍的数组，分别是：同类域 捕食域 天敌域

#include <iostream>
//同类 捕食 天敌

using namespace std;

const int N = 50010;

int f[3 * N];
int res;

int find(int x)
{
    return f[x] = (f[x] == x ? x : find(f[x]));
}

void merge(int a , int b)
{
    a = find(a) , b = find(b);
    f[a] = b;
}

int main()
{
    int n , k;
    cin >> n >> k;

    for(int i = 1 ; i <= 3 * n ; i++) f[i] = i;

    while(k--)
    {
        int d , a , b;
        cin >> d >> a >> b;
        if(a > n || b > n) res ++;
        else if(d == 1)
        {
            if(find(a) == find(b + n) || find(a) == find(b + n + n) ) res++;
            else merge(a , b) , merge(a + n , b + n) , merge(a + n + n , b + n + n);
        }
        else if(d == 2)
        {
            if(a == b || find(a) == find(b) || find(a) == find(b + n)) res++;
            else merge(a , b + n + n) , merge(a + n , b) , merge(a + n + n , b + n);
        }
    }

    cout << res << endl;

    return 0;
}