#include <bits/stdc++.h>
using namespace std;
int main() {
  string s = "abcdefghijklmnopqrstuvwxyz";
  string s2 = "";
  int n, k;
  cin >> n >> k;
  for (int i = 0; i < n; i++) s2 += s[i % k];
  cout << s2 << endl;
  return 0;
}
