#include <bits/stdc++.h>
using namespace std;
int main() {
  int n, k;
  cin >> n >> k;
  int count = 0;
  while (count != n) {
    int c = 'a';
    for (int i = 0; i < k; i++) {
      cout << (char)(c + i);
      count++;
      if (count == n) break;
    }
  }
}
