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: #!/usr/bin/env python
  #from __future__ import division, print_function
  import math
  import os
  import sys
  from io import BytesIO, IOBase
  M = 10 ** 9 + 7
  import heapq
  import bisect
  from functools import lru_cache
  from collections import *
  if sys.version_info[0] < 3:
      from __builtin__ import xrange as range
      from future_builtins import ascii, filter, hex, map, oct, zip
  # sys.setrecursionlimit(10**6)
  # region fastio
  BUFSIZE = 8192
  class FastIO(IOBase):
      newlines = 0
      def __init__(self, file):
          self._fd = file.fileno()
          self.buffer = BytesIO()
          self.writable = "x" in file.mode or "r" not in file.mode
          self.write = self.buffer.write if self.writable else None
      def read(self):
          while True:
              b = os.read(self._fd, max(os.fstat(self._fd).st_size, BUFSIZE))
              if not b:
                  break
              ptr = self.buffer.tell()
              self.buffer.seek(0, 2), self.buffer.write(b), self.buffer.seek(ptr)
          self.newlines = 0
          return self.buffer.read()
      def readline(self):
          while self.newlines == 0:
              b = os.read(self._fd, max(os.fstat(self._fd).st_size, BUFSIZE))
              self.newlines = b.count(b"\n") + (not b)
              ptr = self.buffer.tell()
              self.buffer.seek(0, 2), self.buffer.write(b), self.buffer.seek(ptr)
          self.newlines -= 1
          return self.buffer.readline()
      def flush(self):
          if self.writable:
              os.write(self._fd, self.buffer.getvalue())
              self.buffer.truncate(0), self.buffer.seek(0)
  class IOWrapper(IOBase):
      def __init__(self, file):
          self.buffer = FastIO(file)
          self.flush = self.buffer.flush
          self.writable = self.buffer.writable
          self.write = lambda s: self.buffer.write(s.encode("ascii"))
          self.read = lambda: self.buffer.read().decode("ascii")
          self.readline = lambda: self.buffer.readline().decode("ascii")
  def print(*args, **kwargs):
      """Prints the values to a stream, or to sys.stdout by default."""
      sep, file = kwargs.pop("sep", " "), kwargs.pop("file", sys.stdout)
      at_start = True
      for x in args:
          if not at_start:
              file.write(sep)
          file.write(str(x))
          at_start = False
      file.write(kwargs.pop("end", "\n"))
      if kwargs.pop("flush", False):
          file.flush()
  if sys.version_info[0] < 3:
      sys.stdin, sys.stdout = FastIO(sys.stdin), FastIO(sys.stdout)
  else:
      sys.stdin, sys.stdout = IOWrapper(sys.stdin), IOWrapper(sys.stdout)
  input = lambda: sys.stdin.readline().rstrip("\r\n")
  def inp(): return sys.stdin.readline().rstrip("\r\n")  # for fast input
  def out(var): sys.stdout.write(str(var))  # for fast output, always take string
  def lis(): return list(map(int, inp().split()))
  def stringlis(): return list(map(str, inp().split()))
  def sep(): return map(int, inp().split())
  def strsep(): return map(str, inp().split())
  def fsep(): return map(float, inp().split())
  def inpu(): return int(inp())
  def valid(arr,n,c,mid):
      s=0
      p=arr[0]
      for i in range(1,n):
          temp=arr[i]-p
          if temp>=mid:
              s+=1
              p=arr[i]
      #print(s)
      if s>=c-1:
          return True
      return False
  def fun(n):
      s=str(n)
      ans=0
      for i in range(len(s)):
          p=int(s[i])
          ans+=math.factorial(p)
      ans=str(ans)
      res=0
      for  i in range(len(ans)):
          res+=int(ans[i])
      return res
  def fun4(n):
          m=1
          while(n&m):
              n^=m
              m<<=1
          n=n^m
          return n
  def main():
      t=1
      t=inpu()
      for _ in range(t):
          n=inpu()
          if n == 1:
              print("a")
          elif n % 2 == 0:
              print("a" * (n // 2) + "b" + "a" * (n // 2 - 1))
          else:
              print("a" * (n // 2) + "bc" + "a" * (n // 2 - 1))
  if __name__ == '__main__':
      main()
  