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Huhu_Miao: 2024-12-31 23:26:33
/**
 *    author:  Huhu_Miao
 *    created: 2024.12.31 23:24:00 (UTC+8)
 *    并查集卡常并非刚需，DFS暴力亲测可过！
**/

#include<vector>
#include<deque>
#include<iostream>

void dfs(const auto g, auto& vis, int id){
    vis[id] = true;
    for(const auto neighbor : g[id]){
        if(!vis[neighbor]) dfs(g,vis,neighbor);
    }
}

void solve(){
    int n , m ;
    std::cin >> n >> m;

    std::vector<std::vector<int>> g(n+1);
    std::deque<bool> vis(n+1,false);

    for(int i = 0 ; i < m ; i++){
        int from , to;
        std::cin >> from >> to;
        g[from].push_back(to);
        g[to].push_back(from);
    }

    int cnt = 0;
    
    for(int i = 1 ; i < n+1 ; i++){
        if(!vis[i]){
            dfs(g,vis,i);
            cnt++;
        }
    }

    std::cout << cnt << '\n';
}

int main(){
    std::ios::sync_with_stdio(false); std::cin.tie(nullptr);
    int T; std::cin>>T;
    while(T--) solve();
    return 0;
}