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