10681

#include <cstdio>
#include <vector>
#include <cstring>
#include <iostream>
using namespace std;
#define mem(x,y) memset(x,y,sizeof(x))
#define READ(f) freopen(f, "r", stdin)

/**  Main Code **/

#define Max 500
#define No_city 100
#define No_days 200

bool visited[No_city + 1][No_days + 1];
bool dp[No_city + 1][No_days + 1];
vector<int> adj[Max + 10];
int cities, edge, start, end, days;

bool tsp (int city, int days) {
    if(days == 0) {
        if (city == end)
            return true;
        else
            return false;
    }

    if (city == end)
        return false;

    if (visited[city][days])
        return visited[city][days];

    visited[city][days] = true;
    bool ans = false;

    for (int i = 0; i < (int) adj[city].size(); i++) {
        //ans = ans || tsp(adj[city][i], days - 1);
    ans = tsp(adj[city][i], days - 1);
        if(ans == true)
            break;
    }
    return dp[city][days] = ans;
}

int main() {
#ifndef ONLINE_JUDGE
    READ("input.txt");
#endif
    int u, v;
    while(scanf("%d%d", &cities, &edge) != EOF and cities and edge) {
        for (int i = 0; i < edge; i++) {
            scanf("%d %d", &u, &v);
            adj[u].push_back(v);
            adj[v].push_back(u);
        }
        scanf("%d%d%d", &start, &end, &days);
        mem(visited, false);
        if(tsp(start, days)) {
            printf("Yes, Teobaldo can travel.\n");
        } else {
            printf("No, Teobaldo can not travel.\n");
        }
        for (int i = 0; i < cities + 5; i++) {
            adj[i].clear();
        }
    }
    return 0;
}