#include <bits/stdc++.h>

using LL = long long;

const int N = 2e5 + 7;

LL sum[N];
int n, m, a[N], set[N];

int find(int x) {
  return set[x] == x ? x : set[x] = find(set[x]);
}

void uni(int x, int y) {
  x = find(x);
  y = find(y);
  if(x != y) {
    sum[y] += sum[x];
    set[x] = y;
  }
}

void solve() {
  scanf("%d%d", &n, &m);
  for(int i = 1; i <= n; ++i) {
    scanf("%d", &a[i]);
    if(i & 1)
      a[i] = -a[i];
  }
  a[n + 1] = 0;
  for(int i = 1; i <= n + 1; ++i) {
    set[i] = i;
    sum[i] = a[i] - a[i - 1];
  }
  while(m--) {
    int l, r;
    scanf("%d%d", &l, &r);
    uni(l, r + 1);
  }
  for(int i = 1; i <= n + 1; ++i)
    if(set[i] == i && sum[i]) {
      puts("NO");
      return ;
    }
  puts("YES");
}

int main() {

  int cases = 1;
  while(cases--)
    solve();
  
  return 0;
}