10681

#include <algorithm>
#include <bitset>
#include <cctype>
#include <cmath>
#include <complex>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <ctime>
#include <deque>
#include <fstream>
#include <iostream>
#include <list>
#include <climits>
#include <map>
#include <memory>
#include <queue>
#include <set>
#include <sstream>
#include <stack>
#include <string>
#include <utility>
#include <vector>
#include <iomanip>
using namespace std;
/*** typedef ***/
#define MEMSET_INF 127
#define MEMSET_HALF_INF 63
#define stream istringstream
#define rep(i,n) for(__typeof(n) i=0; i<(n); i++)
#define repl(i,n) for(__typeof(n) i=1; i<=(n); i++)
#define FOR(i,a,b) for(__typeof(b) i=(a); i<=(b); i++)
#define INF (1<<30)
#define PI acos(-1.0)
#define pb push_back
#define ppb pop_back
#define all(x) x.begin(),x.end()
#define mem(x,y) memset(x,y,sizeof(x))
#define memsp(x) mem(x,MEMSET_INF)
#define memdp(x) mem(x,-1)
#define memca(x) mem(x,0)
#define eps 1e-9
#define pii pair<int,int>
#define pmp make_pair
#define ft first
#define sd second
#define vi vector<int>
#define vpii vector<pii>
#define si set<int>
#define msi map<string , int >
#define mis map<int , string >
typedef long long i64;
typedef unsigned long long ui64;
/** function **/
#define SDi(x) sf("%d",&x)
#define SDl(x) sf("%lld",&x)
#define SDs(x) sf("%s",x)
#define SD2(x,y) sf("%d%d",&x,&y)
#define SD3(x,y,z) sf("%d%d%d",&x,&y,&z)
#define pf printf
#define print(x) pf("%d ", x)
#define println(x) pf("%d\n", x)
#define sf scanf
#define READ(f) freopen(f, "r", stdin)

#define Max 210

int C, L;
int S, E, D;
bool vis[Max][Max];
vector <int> adj[Max];

bool call(int u, int d) {
    //if(d == 0) return true;
    if(d == 1) {
        rep(i, adj[u].size())
        if(adj[u][i] == E) return true;
        return false;
    }
    if(adj[u].size() == 1 && adj[u][0] == E)
        return false;
    rep(i, adj[u].size()) {
        bool ans = call(adj[u][i], d - 1);
        if(ans) return true;
    }
    return false;
}

int main() {
#ifndef ONLINE_JUDGE
    READ("input.txt");
#endif
    int u, v;
    while(SD2(C, L) && C && L) {
        rep(i, L) {
            SD2(u, v);
            adj[u].pb(v);
            adj[v].pb(u);
        }
        SD3(S, E, D);
        if(D == 0 || L == 0) {
            pf("No, Teobaldo can not travel.\n");
        } else {
            if(call(S, D)) {
                pf("Yes, Teobaldo can travel.\n");
            } else {
                pf("No, Teobaldo can not travel.\n");
            }
        }

        rep(i, C + 10) adj[i].clear();
    }
    return 0;
}