#include <bits/stdc++.h>
using namespace std;
const long long MOD = 1000000007;
const long long inf = 2e18;
void __print(int x) { cerr << x; }
void __print(long x) { cerr << x; }
void __print(long long x) { cerr << x; }
void __print(unsigned x) { cerr << x; }
void __print(unsigned long x) { cerr << x; }
void __print(unsigned long long x) { cerr << x; }
void __print(float x) { cerr << x; }
void __print(double x) { cerr << x; }
void __print(long double x) { cerr << x; }
void __print(char x) { cerr << '\'' << x << '\''; }
void __print(const char *x) { cerr << '\"' << x << '\"'; }
void __print(const string &x) { cerr << '\"' << x << '\"'; }
void __print(bool x) { cerr << (x ? "true" : "false"); }
template <typename T, typename V>
void __print(const pair<T, V> &x) {
  cerr << '{';
  __print(x.first);
  cerr << ',';
  __print(x.second);
  cerr << '}';
}
template <typename T>
void __print(const T &x) {
  int f = 0;
  cerr << '{';
  for (auto &i : x) cerr << (f++ ? "," : ""), __print(i);
  cerr << "}";
}
void _print() { cerr << "]\n"; }
template <typename T, typename... V>
void _print(T t, V... v) {
  __print(t);
  if (sizeof...(v)) cerr << ", ";
  _print(v...);
}
void setIO(string s) {
  if (s.length() == 0) return;
  freopen((s + ".in").c_str(), "r", stdin);
  freopen((s + ".out").c_str(), "w", stdout);
}
void solve() {
  int n, k;
  cin >> n >> k;
  vector<int> ans(n);
  int d = n / k;
  int p = 0;
  int ct = 1;
  for (int i = 0; i < d; i++) {
    ct = 1;
    for (int j = 0; j < k; j++) {
      ans[p] = ct;
      p++;
      ct++;
    }
  };
  ct = 1;
  for (int i = p; i < n; i++) {
    ;
    ans[i] = ct;
    ct++;
  }
  for (int i = 0; i < n; i++) {
    cout << (char)('a' + ans[i] - 1);
  }
  cout << endl;
}
int main() {
  ios_base::sync_with_stdio(0), cin.tie(0), cout.tie(0);
  int t = 1;
  while (t--) {
    solve();
  }
  return 0;
}
