#include <bits/stdc++.h>
using namespace std;
long long n, a[100005];
int main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  cin >> n;
  string s;
  cin >> s;
  if (n == 1 && s[0] == '1')
    cout << "Yes";
  else if (n == 1)
    cout << "No";
  else if (n == 2 && s[0] != s[1])
    cout << "Yes";
  else if (n == 2)
    cout << "No";
  else {
    if (s[0] == '0' && s[1] == '0')
      cout << "No";
    else if (s[n - 1] == '0' && s[n - 2] == '0')
      cout << "No";
    else {
      for (int i = 0; i < n - 2; ++i) {
        if (s[i] == '0' && s[i + 1] == '0' && s[i + 2] == '0') {
          cout << "No";
          return 0;
        } else if (s[i] == '1' && s[i + 1] == '1') {
          cout << "No";
          return 0;
        } else if (s[i + 1] == '1' && s[i + 2] == '1') {
          cout << "No";
          return 0;
        }
      }
      cout << "Yes";
    }
  }
  return 0;
}
