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: try:
          import sys
          from functools import lru_cache, cmp_to_key
          from heapq import merge, heapify, heappop, heappush
          from math import *
          from collections import defaultdict as dd, deque, Counter as C
          from itertools import combinations as comb, permutations as perm
          from bisect import bisect_left as bl, bisect_right as br, bisect, insort
          from time import perf_counter
          from fractions import Fraction
          import copy
          from copy import deepcopy
          import time
          starttime = time.time()
          mod = int(pow(10, 9) + 7)
          mod2 = 998244353
  
          def data(): return sys.stdin.readline().strip()
          def out(*var, end="\n"): sys.stdout.write(' '.join(map(str, var))+end)
          def L(): return list(sp())
          def sl(): return list(ssp())
          def sp(): return map(int, data().split())
          def ssp(): return map(str, data().split())
          def l1d(n, val=0): return [val for i in range(n)]
          def l2d(n, m, val=0): return [l1d(n, val) for j in range(m)]
          def A2(n,m): return [[0]*m for i in range(n)]
          def A(n):return [0]*n
          # input = stdin.buffer.readline
          # I = lambda : list(map(int,input().split()))
          # import sys
          # input=sys.stdin.readline
          
  
          sys.stdin = open("input.txt", "r")
          sys.stdout = open("output.txt", "w")
  except:
          pass
  
  
  
  
  
  for _ in range(L()[0]):
          n = int(input())
          if (n == 1):
                  print('a')
          else:
                  s = 'a' * (n // 2)
                  if (n & 1):
                          s += 'bc'
                  else:
                          s += 'b'
                  s += 'a' * (n // 2 - 1)
                  print(s)