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: from bisect import insort,bisect_right,bisect_left
  from sys import stdout, stdin, setrecursionlimit
  from heapq import heappush, heappop, heapify 
  from io import BytesIO, IOBase
  from collections import *
  from itertools import *
  from random import * 
  from string import *
  from queue import *
  from math import *
  from re import *
  from os import *
  
  # sqrt,ceil,floor,factorial,gcd,log2,log10,comb
  
  ####################################---fast-input-output----#########################################
  
  
  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 = read(self._fd, max(fstat(self._fd).st_size, 8192))
              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 = read(self._fd, max(fstat(self._fd).st_size, 8192))
              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:
              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")
  
  
  stdin, stdout = IOWrapper(stdin), IOWrapper(stdout)
  graph, mod, szzz =  {}, 10**9 + 7, lambda: sorted(zzz())
  def getStr(): return input()
  def getInt(): return int(input())
  def listStr(): return list(input())
  def getStrs(): return input().split()
  def isInt(s): return '0' <= s[0] <= '9'
  def input(): return stdin.readline().strip()
  def zzz(): return [int(i) for i in input().split()]
  def output(answer, end='\n'): stdout.write(str(answer) + end)
  def lcd(xnum1, xnum2): return (xnum1 * xnum2 // gcd(xnum1, xnum2))
  
  
  def getPrimes(N = 10**5):
      SN = int(sqrt(N))
      sieve = [i for i in range(N+1)]
      sieve[1] = 0
      for i in sieve:
          if i > SN:
              break
          if i == 0:
              continue
          for j in range(2*i, N+1, i):
              sieve[j] = 0
      prime = [i for i in range(N+1) if sieve[i] != 0] 
      return prime
  def primeFactor(n,prime=getPrimes()):
      lst = []
      mx=int(sqrt(n))+1
      for i in prime:
          if i>mx:break
          while n%i==0:
              lst.append(i)
              n//=i
      if n>1:
          lst.append(n)
      return lst    
  
  dx = [-1, 1, 0, 0, 1, -1, 1, -1]
  dy = [0, 0, 1, -1, 1, -1, -1, 1]
  daysInMounth = [31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31]
  
  
  #################################################---Some Rule For Me To Follow---#################################
  """
      --instants of Reading problem continuously try to understand them.
  
      --Try & again try, maybe you're just one statement away!
  
  """
  ##################################################---START-CODING---###############################################
  
  import math
   
  
  def maximumXOR(n, l, r):
      x = 0
  
      for i in range(31, -1, -1):
          if (n & (1 << i)): # Set bit
              if  (x + (1 << i) - 1 < l):
                  x ^= (1 << i)
          else: # Unset bit
              if (x ^ (1 << i)) <= r:
                  x ^= (1 << i)
     
      return x
   
  
  
  num = getInt()
  
  for _ in range(num):
      n = getInt()
  
      ans1 = 'a'*(n//2)
      if n%2==0:
          mid='b'
      else:
          mid='bc'
      print((ans1+mid+ans1[:-1])[:n])