import sys
sys.setrecursionlimit(100000000)
MOD = 10 ** 9 + 7
INF = 10 ** 15

def main():  
    N,M = map(int,input().split())
    A = list(map(int,input().split()))
    G = [[] for _ in range(N)]
    for _ in range(M):
        a,b = map(int,input().split())
        a -= 1
        b -= 1
        G[a].append(b)
        G[b].append(a)
    
    flag = False
    for i in range(N):
        stack = [(0,i,-1)]
        while stack:
            time,v,before = stack.pop()
            if time == 1:
                for e in G[v]:
                    if e == before:
                        continue
                    if (A[i] > A[v] and A[e] > A[v] and A[i] != A[e]) or (A[i] < A[v] and A[e] < A[v] and A[e] != A[i]):
                        flag = True
                        break 
            elif time == 0:
                for e in G[v]:
                    if e == before:
                        continue
                    stack.append((1,e,v))
            if flag:
                break
        if flag:
            break
    print('YES' if flag else 'NO')
if __name__ == '__main__':
    main()