#include <stdio.h>
#include <algorithm>
#include <iostream>
#include <string>
#include <vector>
#include <functional>
#include <map>
#include <iomanip>
#include <math.h> 
#include <stack>
#include <queue>
#include <bitset>
#include <cstdlib>
#include <tuple>
#include <cctype>
#include <ctype.h>
#include <set>

using namespace std;


int main() {
	int  i, j, k;
	long n, m;
	vector<long>a(2005, -1);
	vector<pair<long, long>>v(17000, make_pair(999999, 999999));
	vector<vector<long>>flag(1005, vector<long>(1005, false));
	vector<long>flag2(11111, false);


	cin >> n >> m;

	for (i = 1; i <= n; i++) {
		cin >> a[i];
	}

	for (i = 0; i < m*2; i++) {
		long u1, u2;
		cin >> u1 >> u2;
		v[i].first = u1;
		v[i].second = u2;
		i++;
		v[i].first = u2;
		v[i].second = u1;
	}

	sort(v.begin(), v.end());


	for (i = 0; i < m * 2; i++) {
		long num1, num2, num3;
		num1 = a[v[i].first];
		flag2[v[i].first] = true;

		for (j = 0; j < m * 2; j++) {
			if (v[i].second == v[j].first && flag2[v[i].second] == false) {
				num2 = a[v[j].first];
				flag2[v[j].first] = true;

				for (k = 0; k < m * 2; k++) {
					if (v[j].second == v[k].first && flag2[v[j].second]==false) {
						num3 = a[v[k].first];
						//flag2[v[k].first] = true;

						//cout << "num1->" << num1 << "num2->" << num2 << "num3->" << num3 << endl;


						if (((num1<num3) && (num3<num2)) || ((num3>num1)&&(num1>num2)) || ((num3<num1)&&(num1<num2)) || ((num1>num3)&&(num3>num2))) {
							cout << "YES" << endl;
							getchar();
							getchar();
							return 0;
						}
					}
				}
				flag2[v[j].first] = false;
			}
		}

		flag2[v[i].first] = false;
	}

	cout << "NO" << endl;

	getchar();
	getchar();
	return 0;
}