#include <bits/stdc++.h>
using namespace std;
int main() {
  int n, k;
  cin >> n >> k;
  string s;
  for (int i = 0, j = 0; i < n; i++, j++) {
    if (j == k) j = 0;
    char x = 97 + j;
    s += x;
  }
  cout << s << endl;
  return 0;
}
