#include <bits/stdc++.h>
using namespace std;
void speed() {
  ios::sync_with_stdio(0);
  cin.tie(0);
  cout.tie(0);
}
void convertString(string &s, char t) {
  if (t == 'L') {
    for (int i = 0; s[i] != '\0'; i++)
      if (s[i] >= 65 && s[i] <= 90) s[i] += 32;
  } else {
    for (int i = 0; s[i] != '\0'; i++)
      if (s[i] >= 97 && s[i] <= 122) s[i] -= 32;
  }
}
int compare_two_values(double a, double b) {
  if (fabs(a - b) <= 1e-10) return 0;
  return a > b ? 1 : -1;
}
int main() {
  speed();
  short n, d, c = 0;
  cin >> n >> d;
  for (char i = 'a'; n > 0; n--) {
    cout << i;
    c++;
    if (c == 26 || c == d)
      c = 0, i = 'a';
    else
      i++;
  }
  return 0;
}
