DFS

#include <iostream>
#include <vector>

using namespace std;

const int MAX = 100;
vector<int> adj[MAX];
bool visited[MAX];

void DFS(int u) {
  visited[u] = true;
  cout << u << " ";
  for (int i = 0; i < adj[u].size(); i++) {
    int v = adj[u][i];
    if (!visited[v]) {
      DFS(v);
    }
  }
}

int main() {
  int n, m, s;
  cin >> n >> m >> s;
  for (int i = 0; i < m; i++) {
    int u, v;
    cin >> u >> v;
    adj[u].push_back(v);
    adj[v].push_back(u);
  }
  DFS(s);
  return 0;
}