#include <bits/stdc++.h>
using namespace std;
int main() {
  int n;
  cin >> n;
  vector<int> a(n);
  for (int i = 0; i < n; i++) cin >> a[i];
  int pen = 0;
  for (int i = 0; i < n; i++) {
    if (pen) {
      if (a[i])
        a[i]--;
      else {
        cout << "NO";
        return 0;
      }
      pen = 0;
    }
    if (a[i] % 2) pen = 1;
    if (i == n - 1) {
      if (pen)
        cout << "NO";
      else
        cout << "YES";
    }
  }
  return 0;
}
