dfs

#include <bits/stdc++.h>
using namespace std;

#define MAXPEEKSNR 100
int peeks, links;
vector<int> graph[MAXPEEKSNR];
vector<bool> visited;

int dfs(int node)
{
    int visnr = 1;
    visited[node] = true;
    for (int i = 0; i < (int)graph[node].size(); i++)
        if (!visited[graph[node][i]])
            visnr += dfs(graph[node][i]);
    return visnr;
}

int main()
{
    cin >> peeks >> links;
    int node;
    visited.resize(peeks + 1);
    for (int i = 0; i < links; i++)
    {
        int x, y;
        cin >> x >> y;
        graph[x].push_back(y);
        graph[y].push_back(x);
        node = x;
    }

    int visnr = dfs(node);
    cout << endl << visnr;

    return 0;
}