#include #include #include
using namespace std;
int n;string x;
int main(){ cin >> n >> x; sort(x.begin(), x.end()); int first_not_zero = -1; for (int i = 0; i < n; ++i) { if(x[i] != '0') { first_not_zero = i; break; } } if(first_not_zero != -1) swap(x[0], x[first_not_zero]); cout << x << endl; return 0;}