n, m, k, s, t = map(int, input().split())
s -= 1
t -= 1
g = [[] for _ in range(n)]
for _ in range(m):
    u, v = map(int, input().split())
    u -= 1
    v -= 1
    g[u].append(v)
    g[v].append(u)
ans = True if k % 2 else bool(g[s] or g[t])
print('Yes' if ans else 'No')