func_code_string: #include <bits/stdc++.h>   using namespace std;   int n, m, a[2000000 + 100];   int main() {     cin >> n >> m;     if ((m < n - 1) || (m > 2 * (n + 1))) {       cout << -1 << endl;       return 0;     }     for (int i = 1; i <= n; i++) a[2 * i] = 0;     for (int i = 2; i <= n; i++) a[2 * i - 1] = 1;     m = m - (n - 1);     for (int i = 2; i <= n; i++) {       if (m == 0) break;       a[2 * i - 1] = 11, m--;     }     if (m == 1) cout << 1;     if (m == 2) cout << 11;     if (m == 3) cout << 11;     if (m == 4) cout << 11;     for (int i = 2; i <= 2 * n; i++) cout << a[i];     if (m == 3) cout << 1;     if (m == 4) cout << 11;     return 0;   }   