#include <bits/stdc++.h>
using namespace std;
int main() {
  int n, k;
  cin >> n >> k;
  if (k != 0) {
    int h = n / k;
    int b = n % k, x = 97;
    for (int i = 0; i < h; i++) {
      x = 97;
      for (int j = 0; j < k; j++) {
        char t = x;
        cout << t;
        if (x == 122) {
          x = 97;
        }
        x++;
      }
    }
    x = 97;
    for (int i = 0; i < b; i++) {
      if (x == 122) {
        x = 0;
      }
      char t = x;
      cout << t;
      x++;
    }
  } else {
    int x = 96;
    for (int i = 0; i < n; i++) {
      x++;
      char t = x;
      cout << t;
      if (x == 122) {
        x = 96;
      }
    }
  }
  return 0;
}
