Problem: Let's define the cost of a string s as the number of index pairs i and j (1 ≤ i < j < |s|) such that s_i = s_j and s_{i+1} = s_{j+1}.

You are given two positive integers n and k. Among all strings with length n that contain only the first k characters of the Latin alphabet, find a string with minimum possible cost. If there are multiple such strings with minimum cost — find any of them.

Input

The only line contains two integers n and k (1 ≤ n ≤ 2 ⋅ 10^5; 1 ≤ k ≤ 26).

Output

Print the string s such that it consists of n characters, each its character is one of the k first Latin letters, and it has the minimum possible cost among all these strings. If there are multiple such strings — print any of them.

Examples

Input


9 4


Output


aabacadbb


Input


5 1


Output


aaaaa

Input


10 26


Output


codeforces

Solution (in JAVA):

Solution:

import java.io.*;
import java.util.*;

public class MinCostString implements Runnable {

   ArrayDeque<Integer>[] tree;
   List<Integer> path = new ArrayList<>();

   void solve() throws IOException {
      int n = ri(), k = ri();
      // We will use Eulerian cycle to construct the string having unique pairs
      tree = new ArrayDeque[k];
      Arrays.setAll(tree, o -> new ArrayDeque<>());
      for (int i = 0; i < k; i++) {
         tree[i].add(i);
         for (int j = i + 1; j < k; j++) {
            tree[i].add(j);
            tree[j].add(i);
         }
      }

      // Find Eulerian Cycle( It always exist as it is strongly connected )
      dfs(0);
      sbr.append('a');
      path.remove(0);
      for (int i = 0; i < n - 1; i++) {
         sbr.append((char) (path.get(i % path.size()) + 'a'));
      }
      print(sbr.toString());
   }

   void dfs(int u) {
      while (!tree[u].isEmpty()) {
         dfs(tree[u].pollLast());
      }

      path.add(u);
   }

   /************************************************************************************************************************************************/
   public static void main(String[] args) throws IOException {
      new Thread(null, new MinCostString(), "1").start();
   }

   static PrintWriter out = new PrintWriter(System.out);
   static Reader read = new Reader();
   static StringBuilder sbr = new StringBuilder();
   static int mod = (int) 1e9 + 7;
   static int dmax = Integer.MAX_VALUE;
   static long lmax = Long.MAX_VALUE;
   static int dmin = Integer.MIN_VALUE;
   static long lmin = Long.MIN_VALUE;

   @Override
   public void run() {
      try {
         solve();
         out.close();
      } catch (IOException e) {
         e.printStackTrace();
         System.exit(1);
      }
   }

   static class Reader {
      private byte[] buf = new byte[1024];
      private int index;
      private InputStream in;
      private int total;

      public Reader() {
         in = System.in;
      }

      public int scan() throws IOException {
         if (total < 0)
            throw new InputMismatchException();
         if (index >= total) {
            index = 0;
            total = in.read(buf);
            if (total <= 0)
               return -1;
         }
         return buf[index++];
      }

      public int intNext() throws IOException {
         int integer = 0;
         int n = scan();
         while (isWhiteSpace(n))
            n = scan();
         int neg = 1;
         if (n == '-') {
            neg = -1;
            n = scan();
         }
         while (!isWhiteSpace(n)) {
            if (n >= '0' && n <= '9') {
               integer *= 10;
               integer += n - '0';
               n = scan();
            } else
               throw new InputMismatchException();
         }
         return neg * integer;
      }

      public double doubleNext() throws IOException {
         double doub = 0;
         int n = scan();
         while (isWhiteSpace(n))
            n = scan();
         int neg = 1;
         if (n == '-') {
            neg = -1;
            n = scan();
         }
         while (!isWhiteSpace(n) && n != '.') {
            if (n >= '0' && n <= '9') {
               doub *= 10;
               doub += n - '0';
               n = scan();
            } else
               throw new InputMismatchException();
         }
         if (n == '.') {
            n = scan();
            double temp = 1;
            while (!isWhiteSpace(n)) {
               if (n >= '0' && n <= '9') {
                  temp /= 10;
                  doub += (n - '0') * temp;
                  n = scan();
               } else
                  throw new InputMismatchException();
            }
         }
         return doub * neg;
      }

      public String read() throws IOException {
         StringBuilder sb = new StringBuilder();
         int n = scan();
         while (isWhiteSpace(n))
            n = scan();
         while (!isWhiteSpace(n)) {
            sb.append((char) n);
            n = scan();
         }
         return sb.toString();
      }

      private boolean isWhiteSpace(int n) {
         if (n == ' ' || n == '\n' || n == '\r' || n == '\t' || n == -1)
            return true;
         return false;
      }
   }

   static void shuffle(int[] aa) {
      int n = aa.length;
      Random rand = new Random();
      for (int i = 1; i < n; i++) {
         int j = rand.nextInt(i + 1);
         int tmp = aa[i];
         aa[i] = aa[j];
         aa[j] = tmp;
      }
   }

   static void shuffle(int[][] aa) {
      int n = aa.length;
      Random rand = new Random();
      for (int i = 1; i < n; i++) {
         int j = rand.nextInt(i + 1);
         int first = aa[i][0];
         int second = aa[i][1];
         aa[i][0] = aa[j][0];
         aa[i][1] = aa[j][1];
         aa[j][0] = first;
         aa[j][1] = second;
      }
   }

   static void print(Object object) {
      out.print(object);
   }

   static void println(Object object) {
      out.println(object);
   }

   static int[] iArr(int len) {
      return new int[len];
   }

   static long[] lArr(int len) {
      return new long[len];
   }

   static long min(long a, long b) {
      return Math.min(a, b);
   }

   static int min(int a, int b) {
      return Math.min(a, b);
   }

   static long max(Long a, Long b) {
      return Math.max(a, b);
   }

   static int max(int a, int b) {
      return Math.max(a, b);
   }

   static int ri() throws IOException {
      return read.intNext();
   }

   static long rl() throws IOException {
      return Long.parseLong(read.read());
   }

   static String rs() throws IOException {
      return read.read();
   }

   static char rc() throws IOException {
      return rs().charAt(0);
   }

   static double rd() throws IOException {
      return read.doubleNext();
   }
}