#include <bits/stdc++.h>
using namespace std;
struct GetChar {
  char sl[26];
  int iter = 0, k;
  GetChar(int k) {
    this->k = k;
    for (int i = 0; i < k; i++) {
      sl[i] = i + 'a';
    }
  }
  const char next() {
    if (iter >= k) iter = 0;
    return sl[iter++];
  }
};
int main() {
  int n, k;
  scanf("%d%d", &n, &k);
  GetChar gch(k);
  for (int i = 0; i < n; i++) {
    printf("%c", gch.next());
  }
}
