#include <bits/stdc++.h>   using namespace std;   string onezero(int n) {     string s =  1 ;     for (int i = 1; i < n; ++i) {       s +=  0 ;     }     return s;   }   string findSum(string str1, string str2) {     if (str1.length() > str2.length()) swap(str1, str2);     string str =   ;     int n1 = str1.length(), n2 = str2.length();     reverse(str1.begin(), str1.end());     reverse(str2.begin(), str2.end());     int carry = 0;     for (int i = 0; i < n1; i++) {       int sum = ((str1[i] -  0 ) + (str2[i] -  0 ) + carry);       str.push_back(sum % 10 +  0 );       carry = sum / 10;     }     for (int i = n1; i < n2; i++) {       int sum = ((str2[i] -  0 ) + carry);       str.push_back(sum % 10 +  0 );       carry = sum / 10;     }     if (carry) str.push_back(carry +  0 );     reverse(str.begin(), str.end());     return str;   }   int main() {     ios_base::sync_with_stdio(NULL);     cin.tie(NULL);     cout.tie(NULL);     int l;     string s, ans;     cin >> l >> s;     if (s.size() % l != 0) {       string zero = onezero(l);       for (int i = 0; i < s.size() / l + 1; ++i) {         ans += zero;       }     } else {       string temp = s.substr(0, l);       for (int i = 0; i < s.size() / l; ++i) {         ans += temp;       }       if (ans <= s) {         ans =   ;         temp = findSum(temp,  1 );         if (temp.size() != l) {           temp = onezero(l);           ans = onezero(l);         }         for (int i = 0; i < s.size() / l; ++i) {           ans += temp;         }       }     }     cout << ans << endl;   }   