# input import sys input = sys.stdin.readline II = lambda : int(input()) MI = lambda : map(int, input().split()) LI = lambda : [int(a) for a in input().split()] SI = lambda : input().rstrip() LLI = lambda n : [[int(a) for a in input().split()] for _ in range(n)] LSI = lambda n : [input().rstrip() for _ in range(n)] MI_1 = lambda : map(lambda x:int(x)-1, input().split()) LI_1 = lambda : [int(a)-1 for a in input().split()] mod = 998244353 inf = 10 ** 18 + 10 ordalp = lambda s : ord(s)-65 if s.isupper() else ord(s)-97 ordallalp = lambda s : ord(s)-39 if s.isupper() else ord(s)-97 yes = lambda : print("Yes") no = lambda : print("No") yn = lambda flag : print("Yes" if flag else "No") prinf = lambda ans : print(ans if ans < 1000001001001001001 else -1) alplow = "abcdefghijklmnopqrstuvwxyz" alpup = "ABCDEFGHIJKLMNOPQRSTUVWXYZ" alpall = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ" URDL = {'U':(-1,0), 'R':(0,1), 'D':(1,0), 'L':(0,-1)} DIR_4 = [[-1,0],[0,1],[1,0],[0,-1]] DIR_8 = [[-1,0],[-1,1],[0,1],[1,1],[1,0],[1,-1],[0,-1],[-1,-1]] DIR_BISHOP = [[-1,1],[1,1],[1,-1],[-1,-1]] prime60 = [2,3,5,7,11,13,17,19,23,29,31,37,41,43,47,53,59] sys.set_int_max_str_digits(0) # sys.setrecursionlimit(10**6) # import pypyjit # pypyjit.set_param('max_unroll_recursion=-1') from collections import defaultdict,deque from heapq import heappop,heappush from bisect import bisect_left,bisect_right DD = defaultdict BSL = bisect_left BSR = bisect_right n, m, k, s, t = MI() s -= 1 t -= 1 assert s != t e = [[0] * n for i in range(n)] for i in range(m): u, v = MI_1() e[u][v] = 1 e[v][u] = 1 if k & 1: yes() exit() p = sum(e[s]) - e[s][t] q = sum(e[t]) - e[t][s] if p or q: yes() exit() if e[s][t] == 0: no() exit() def solve(s): d = [[inf, inf] for i in range(n)] d[s][0] = 0 st = deque([(s, 0)]) while st: u, f = st.popleft() nd = d[u][f] for v in range(n): if e[u][v] and d[v][f^1] == inf: d[v][f^1] = nd+1 st.append((v, f^1)) return d[s][1] r = inf for i in range(n): r = min(r, solve(i)) yn(r <= k-3)