hdu1213简单并差集

  第一次做并差集，算是留个纪念吧~~

#include <cstdio>
#include <cstring>
#include <iostream>
#include <algorithm>
using namespace std;
const int MAXN = 1010;
int M, N;
int parent[MAXN];

int myfind(int i) {
    int r = i;
    while (parent[r] != r) {
        r = parent[r];
    }
    return r;
}

inline void merge(int a, int b) {
    if (a < b) {
        parent[b] = a;
    } else {
        parent[a] = b;
    }
}

int main() {
    int T, a, b, ans;
    scanf("%d", &T);
    while (T--)
    {
        scanf("%d%d", &N, &M);
        for (int i = 1; i <= N; i++)
        {
            parent[i] = i;
        }
        for (int i = 0; i < M; i++)
        {
            scanf("%d%d", &a, &b);
            merge(myfind(a), myfind(b));
        }
        ans = 0;
        for (int i = 1; i <= N; i++)
        {
            if (parent[i] == i)
            {
                ans++;
            }
        }
        printf("%d\n", ans);
    }
    return 0;
}