#include <bits/stdc++.h>
using namespace std;
string a = "abcdefghijklmnopqrstuvwxyz";
int main() {
  int n, k;
  cin >> n >> k;
  string ans;
  for (int i = 0; i < n; i++) ans = ans + a[i % k];
  cout << ans << endl;
  return 0;
}
