N,M = map(int,input().split())
node = [0]+list(map(int,input().split()))
side = {}

def kadomatu():
    for i in range(1,N+1):
        mid = node[i]
        nd = side.get(i,[])
        len_n = len(nd)
        if len_n>1:
            for a in range(1,len_n):
                for b in range(a):
                    l = nd[a]
                    r = nd[b]
                    if (l>mid and r>mid) or (l<mid and r<mid):
                        if l!=mid and r!=mid and l!=r:
                            print("YES")
                            return
    print("NO")

for i in range(M):
    a,b = map(int,input().split())
    side.setdefault(a,[])
    side.setdefault(b,[])
    side[a].append(node[b])
    side[b].append(node[a])
kadomatu()