#!/usr/bin/env python3


# 参考：http://hamayanhamayan.hatenablog.jp/entry/2018/01/06/101220
def has_kadomatsu_path(xs, adj_list):
    for v2, vs in enumerate(adj_list):
        x2 = xs[v2]
        inc = len({xs[v] for v in vs if x2 < xs[v]})
        dec = len({xs[v] for v in vs if x2 > xs[v]})
        if inc >= 2 or dec >= 2:
            return True
    return False


def main():
    n, m = (int(x) for x in input().split())
    xs = [int(x) for x in input().split()]
    adj_list = [set() for _ in range(n)]
    for _ in range(m):
        u, v = (int(z) - 1 for z in input().split())
        adj_list[u].add(v)
        adj_list[v].add(u)
    print("YES" if has_kadomatsu_path(xs, adj_list) else "NO")


if __name__ == '__main__':
    main()