#include <bits/stdc++.h>
using namespace std;
int main() {
  int n;
  while (cin >> n) {
    string str;
    cin >> str;
    bool flag = true;
    if (n < 3) {
      if (n == 1) {
        if (str[0] == '1')
          cout << "Yes" << endl;
        else
          cout << "No" << endl;
      } else {
        if (str != "00" && str != "11")
          cout << "Yes" << endl;
        else
          cout << "No" << endl;
      }
      continue;
    }
    for (int i = 0; i < n - 2; i++) {
      int ans = 0;
      for (int j = i; j < i + 3; j++) {
        ans += str[j] - '0';
      }
      if (ans == 1)
        continue;
      else if (ans == 0 || ans == 3) {
        flag = false;
        break;
      } else {
        if (str[i + 1] != '0') {
          flag = false;
          break;
        }
      }
    }
    if (str[0] == '0' && str[1] == '0' && str[2] == '1') flag = false;
    if (str[n - 1] == '0' && str[n - 2] == '0' && str[n - 3] == '1')
      flag = false;
    if (flag)
      cout << "Yes" << endl;
    else
      cout << "No" << endl;
  }
}
