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