#yuki629

N,M=map(int,raw_input().split())
A=map(int,raw_input().split())
E=[[] for i in xrange(N)]
for i in xrange(M):
 a,b=map(int,raw_input().split())
 a,b=a-1,b-1
 E[a].append(b)
 E[b].append(a)
res='NO'
for cu in xrange(N):
 up=set()
 dn=set()
 for to in E[cu]:
  if A[cu]<A[to]:
   up.add(A[to])
  if A[cu]>A[to]:
   dn.add(A[to])
 if len(up)>=2:
  res='YES'
 if len(dn)>=2:
  res='YES'
print res