Mono probelma divizbilitate

#include <iostream>

using namespace std;

int main()
{
    int n;
    cin >> n;
    int lenght_n = 0, copyN = n;
    while(copyN)
{
    lenght_n++;
    copyN /= 10;
}
   cout << n;
    n -= lenght_n;
   while(n) {
        cout << 0;
   --n;
   }
    return 0;
}