#include<iostream>
#include<string>
#include<vector>
#include<algorithm>
#include<cmath>
#include<functional>
#define For(i, N) for (i = 0; i < N; i++)
#define rep(N) for (int i = 0; i < N; i++)
#define re return 0

using namespace std;
using ll = long long int;
using vi = vector<int>;
using vb = vector<bool>;
using vs = vector<string>;
using pib = pair<int, bool>;
using pii = pair<int, int>;

template<typename T>
void say(T s) {
	cout << s << endl;
}

int main() {
	int N, M;
	cin >> N >> M;
	int A;
	int U, V;
	int i, j;
	vector<int> a;
	vector<pii> u;
	rep(N) {
		cin >> A;
		a.push_back(A);
	}
	rep(M) {
		cin >> U >> V;
		u.push_back({ U - 1,V - 1 });
	}
	for (i = 0; i < M; i++)
		for (j = i; j < M; j++) {
			int x, y, z;
			bool flag = false;
			x = u[i].first;
			y = u[i].second;
			if (u[i].first == u[j].first || u[i].second == u[j].first) {
				z = u[j].second;
				flag = true;
			}
			else if (u[i].first == u[j].second || u[i].second == u[j].second) {
				z = u[j].first;
				flag = true;
			}

			if (flag) {
				if (((x < y&&x < z) || (x > y&&x > z)) && y != z) {
					say("YES");
					re;
				}
			}
		}
	say("NO");

}