N,M=map(int,input().split())
a=list(map(int,input().split()))
a=[0]+a

L=[[]for i in range(N+1)]

for i in range(M):
    u,v=map(int,input().split())
    L[u].append(v)
    L[v].append(u)
ans=0
for i in range(1,N+1):
    for j in L[i]:
        for k in L[j]:
            for l in L[k]:
                if a[k]>a[j]>a[l] or a[k]>a[l]>a[j] or a[j]>a[l]>a[k] or a[l]>a[j]>a[k]:
                    ans+=1
if ans==0:
    print("NO")
else:
    print("YES")