/* -*- coding: utf-8 -*-
 *
 * 3291.cc:  No.3291 K-step Navigation - yukicoder
 */

#include<cstdio>
#include<vector>
#include<queue>
#include<algorithm>

using namespace std;

/* constant */

const int MAX_N = 2000;
const int MAX_N2 = MAX_N * 2;

/* typedef */

using ll = long long;
using vi = vector<int>;
using qi = queue<int>;

/* global variables */

bool es[MAX_N][MAX_N];
vi nbrs[MAX_N];
int ds[MAX_N];

/* subroutines */

/* main */

int main() {
  int n, m, s, t;
  ll k;
  scanf("%d%d%lld%d%d", &n, &m, &k, &s, &t);
  s--, t--;
  for (int i = 0; i < m; i++) {
    int u, v;
    scanf("%d%d", &u, &v);
    u--, v--;
    es[u][v] = es[v][u] = true;
    nbrs[u].push_back(v);
    nbrs[v].push_back(u);
  }

  if ((k & 1) != 0) { puts("Yes"); return 0; }

  if (nbrs[s].empty() && nbrs[t].empty()) { puts("No"); return 0; }

  if ((nbrs[s].size() >= 2 || (nbrs[s].size() == 1 && nbrs[s][0] != t)) &&
      (nbrs[t].size() >= 2 || (nbrs[t].size() == 1 && nbrs[t][0] != s))) {
    puts("Yes"); return 0;
  }
  
  for (int st = 0; st < n; st++)
    if (st != s && st != t) {
      fill(ds, ds + n, -1);
      ds[st] = 0;
      qi q;
      q.push(st);

      while (! q.empty()) {
	int u = q.front(); q.pop();
	for (auto v: nbrs[u]) {
	  if (ds[v] < 0) ds[v] = ds[u] + 1, q.push(v);
	  else if (ds[v] == ds[u]) {
	    if (ds[u] * 2 + 1 <= k - 3) {
	      puts("Yes"); return 0;
	    }
	  }
	}
      }
    }

  puts("No");
  return 0;
}