DFS

#include <bits/stdc++.h>

using namespace std;

const int N = 1003;

int n, m;
int mt[N][N], vis[N];

void dfs(int v) {
    cout << "In v-> " << v << endl;
    vis[v] = 1;
    for (int i = 1; i <= n; i++) {
        if (mt[v][i] == 1 && vis[i] == 0) {
            dfs(i);
        }
    }
    cout << "Out v-> "
}

int main(){
    cin >> n >> m;

    for (int i = 1; i <= m; i++) {
        int u, v;
        cin >> u >> v;
        mt[u][v] = 1;
        mt[v][u] = 1;
    }

    int v;
    cin >> v;

    dfs(v);
}