#include<stdio.h>
int main() {
    int n,m;
    scanf("%d,%d",&n, &m);
    
    if(n <= 0 || m < 0) {
        printf("Invalid input");
        return 0;
    }
    int adj[100][101] = {0};
    for(int i=0 ; i<m ; i++) {
        int u, v;
        scanf("%d,%d",&u, &v);
        if ( u <= 0 || v <= 0 ) {
            printf("Invalid input");
            return 0;
        }
        a[u][v] = 1;
        a[v][u] = 1;
    }
    int start;
    scanf("%d", &start);
    if (start <= 0) {
        printf("Invalid input");
        return 0;
    }
    int visited[100] = {0},q[100];
    int front = 0, rear = 0;
    
    q[rear++] = start;
    visited[start] = 1;
    
    while (front < rear) {
        int p = q[front++];
        printf("%d", p);
        for (int i = 1; i <= n; i++){
            if (a[p][i] && !visited[i]) {
                q[rear++] = i;
                visited[i] = 1;
            }
        }
    }
    return 0;
}