#include <bits/stdc++.h>
template <class T>
bool ckmin(T& a, const T& b) {
  return b < a ? a = b, 1 : 0;
}
template <class T>
bool ckmax(T& a, const T& b) {
  return a < b ? a = b, 1 : 0;
}
using namespace std;
using namespace chrono;
void solve() {
  char ch = 'a';
  int64_t n, k;
  cin >> n >> k;
  int64_t num = ceil((double)n / (double)k);
  string str;
  for (int64_t i = 0; i < k; ++i) str += (ch + i);
  for (int64_t i = 0; i < n; ++i) cout << str[i % k];
  cout << '\n';
}
signed main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  cout.tie(0);
  auto start1 = high_resolution_clock::now();
  int64_t t = 1;
  while (t--) {
    solve();
  }
  auto stop1 = high_resolution_clock::now();
  auto duration = duration_cast<microseconds>(stop1 - start1);
  return 0;
}
