#include <bits/stdc++.h>
using namespace std;
int n, m, a, b, visited[101];
vector<int> adj[101];
 
int go(int here){
    visited[here] = 1;
    int cnt = 1;
    for(int there : adj[here]){
        if(visited[there]) continue;
        cnt += go(there);
    }
    return cnt;
}
 
int main(){
    cin >> n >> m;
    for(int i = 0; i < m; i++){
        cin >> a >> b;
        adj[a].push_back(b);
        adj[b].push_back(a);
    }
 
    cout << go(1) << '\n';
}

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