description: You are given an integer n. Find any string s of length n consisting only of English lowercase letters such that each non-empty substring of s occurs in s an odd number of times. If there are multiple such strings, output any. It can be shown that such string always exists under the given constraints.
  
  A string a is a substring of a string b if a can be obtained from b by deletion of several (possibly, zero or all) characters from the beginning and several (possibly, zero or all) characters from the end.
  
  Input
  
  The first line contains a single integer t (1 ≤ t ≤ 500) — the number of test cases.
  
  The first line of each test case contains a single integer n (1 ≤ n ≤ 10^5).
  
  It is guaranteed that the sum of n over all test cases doesn't exceed 3 ⋅ 10^5.
  
  Output
  
  For each test case, print a single line containing the string s. If there are multiple such strings, output any. It can be shown that such string always exists under the given constraints.
  
  Example
  
  Input
  
  
  4
  3
  5
  9
  19
  
  
  Output
  
  
  abc
  diane
  bbcaabbba
  youarethecutestuwuu
  
  Note
  
  In the first test case, each substring of "abc" occurs exactly once.
  
  In the third test case, each substring of "bbcaabbba" occurs an odd number of times. In particular, "b" occurs 5 times, "a" and "bb" occur 3 times each, and each of the remaining substrings occurs exactly once.
solution: // Don't place your source in a package
  
  
  import javax.swing.*;
  import java.lang.reflect.Array;
  import java.text.DecimalFormat;
  import java.util.*;
  import java.lang.*;
  import java.io.*;
  import java.math.*;
  import java.util.stream.Stream;
  
  
  
  // Please name your class Main
  public class Main {
      static FastScanner fs=new FastScanner();
      static class FastScanner {
          BufferedReader br=new BufferedReader(new InputStreamReader(System.in));
          StringTokenizer st=new StringTokenizer("");
          public String next() {
              while (!st.hasMoreElements())
                  try {
                      st=new StringTokenizer(br.readLine());
                  } catch (IOException e) {
                      e.printStackTrace();
                  }
              return st.nextToken();
          }
          int Int() {
              return Integer.parseInt(next());
          }
  
          long Long() {
              return Long.parseLong(next());
          }
  
          String Str(){
              return next();
          }
      }
  
  
      public static void main (String[] args) throws java.lang.Exception {
          PrintWriter out = new PrintWriter(new BufferedWriter(new OutputStreamWriter(System.out)));
          //reading /writing file
          //Scanner sc=new Scanner(new File("input.txt"));
          //PrintWriter pr=new PrintWriter("output.txt");
  
  
          int T=Int();
          for(int t=0;t<T;t++){
              int n=Int();
  
              Solution sol=new Solution(out);
              sol.solution(n);
          }
          out.close();
  
      }
  
  
      public static int[] Arr(int n){
          int A[]=new int[n];
          for(int i=0;i<n;i++)A[i]=Int();
          return A;
      }
      public static int Int(){
          return fs.Int();
      }
      public static long Long(){
          return fs.Long();
      }
      public static String Str(){
          return fs.Str();
      }
  
  }
  
  
  
  
  
  
  
  
  class Solution {
      PrintWriter out;
      int INF = Integer.MAX_VALUE;
      int MOD = 1000000007;
      long mod = 1000000007;
      public Solution(PrintWriter out) {
          this.out = out;
      }
  
  
  
  
      public void solution(int n) {
          if(n==1){
              out.println("a");
              return;
          }
          if(n==2){
              out.println("ab");
              return;
          }
          if(n==3){
              out.println("abc");
              return;
          }
  
          if(n%2==0){
              String a = go((n-1)/2);
              String b = go((n+1)/2);
              out.println(a+"b"+b);
          }
          else{
              String a = go((n-1-2)/2);
              String b = go((n+1-2)/2);
              out.println(a+"bc"+b);
          }
  
      }
  
      public String go(int t){
          StringBuilder str=new StringBuilder();
          for(int i=0;i<t;i++){
              str.append("a");
          }
          return str.toString();
      }
  
  
  }
  
  
  
  
  
  
  
  
  