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: 
  import java.io.BufferedReader;
  import java.io.IOException;
  import java.io.InputStreamReader;
  import java.io.PrintWriter;
  import java.util.ArrayList;
  import java.util.StringTokenizer;
  
  public class Solver {
  
      public static void main(String[] args) {
          FastReader in = new FastReader();
          PrintWriter out = new PrintWriter(System.out);
          new TaskA().solveD(in, out);
          out.close();
      }
  
      static class TaskA {
          public void solveA(FastReader in, PrintWriter out) {
              int t = in.nextInt();
  
              while (t-- > 0) {
                  int n = in.nextInt();
                  long[] array = in.nextLongArray(n);
                  long result = Long.MIN_VALUE;
  
                  for (int i = 0; i < n - 1; i++) {
                      result = Math.max(result, (array[i] * array[i + 1]));
                  }
                  out.println(result);
              }
          }
  
          public void solveB(FastReader in, PrintWriter out) {
              int t = in.nextInt();
  
              while (t-- > 0) {
                  int n = in.nextInt();
                  int k = in.nextInt();
                  long[] array = in.nextLongArray(n);
                  long max = Long.MIN_VALUE;
  
                  int start = Math.max(0, n - 2 * k);
  
                  for (int i = start; i < n - 1; i++) {
                      for (int j = i + 1; j < n; j++) {
                          max = Math.max(max, (((i + 1l) * (j + 1l)) - (k * (array[i] | array[j]))));
                      }
                  }
                  out.println(max);
              }
          }
  
          public void solveC(FastReader in, PrintWriter out) {
              int t = in.nextInt();
  
              while (t-- > 0) {
                  int n = in.nextInt();
                  int m = in.nextInt();
                  ++m;
  
                  int answer = 0;
  
                  for (int k = 30; k >= 0; k--) {
                      if ((n >> k & 1) == (m >> k & 1)) continue;
                      if ((m >> k & 1) != 0) answer |= 1 << k; n |= 1 << k;
                  }
                  out.println(answer);
              }
          }
  
          public void solveD(FastReader in, PrintWriter out) {
              int t = in.nextInt();
              while (t-- > 0) {
                  int n = in.nextInt();
                  StringBuilder sb = new StringBuilder();
                  int k = n / 2;
  
                  if (n == 1) {
                      sb.append('a');
                  } else {
                      for (int i = 0; i < n; i++) {
                          if (i != k) {
                              sb.append('a');
                          } else {
                              if (n % 2 != 0) i++;
                              sb.append((n % 2 == 0 ? 'b' : "bc"));
                          }
                      }
                  }
                  out.println(sb.toString());
              }
          }
  
          public void solveE(FastReader in, PrintWriter out) {
  
          }
      }
  
      private static long gcd(long a, long b) {
          if (a == 0) {
              return b;
          }
          return gcd(b % a, a);
      }
  
      private static long lcm(long a, long b) {
          return (a * b) / gcd(a, b);
      }
  
      private static int min(int a, int b) {
          return a < b ? a : b;
      }
  
      private static int max(int a, int b) {
          return a > b ? a : b;
      }
  
      private static int min(ArrayList<Integer> list) {
          int min = Integer.MAX_VALUE;
          for (int el : list) {
              if (el < min) {
                  min = el;
              }
          }
          return min;
      }
  
      private static int max(ArrayList<Integer> list) {
          int max = Integer.MIN_VALUE;
          for (int el : list) {
              if (el > max) {
                  max = el;
              }
          }
          return max;
      }
  
      private static int min(int[] list) {
          int min = Integer.MAX_VALUE;
          for (int el : list) {
              if (el < min) {
                  min = el;
              }
          }
          return min;
      }
  
      private static int max(int[] list) {
          int max = Integer.MIN_VALUE;
          for (int el : list) {
              if (el > max) {
                  max = el;
              }
          }
          return max;
      }
  
      private static void fill(int[] array, int value) {
          for (int i = 0; i < array.length; i++) {
              array[i] = value;
          }
      }
  
      static class FastReader {
          BufferedReader br;
          StringTokenizer st;
  
          public FastReader() {
              br = new BufferedReader(new InputStreamReader(System.in));
          }
  
          String next() {
              while (st == null || !st.hasMoreElements()) {
                  try {
                      st = new StringTokenizer(br.readLine());
                  } catch (IOException e) {
                      e.printStackTrace();
                  }
              }
              return st.nextToken();
          }
  
          int nextInt() {
              return Integer.parseInt(next());
          }
  
          long nextLong() {
              return Long.parseLong(next());
          }
  
          double nextDouble() {
              return Double.parseDouble(next());
          }
  
          String nextLine() {
              String str = "";
              try {
                  str = br.readLine();
              } catch (IOException e) {
                  e.printStackTrace();
              }
              return str;
          }
  
          int[] nextIntArray(int n) {
              int[] array = new int[n];
              for (int i = 0; i < n; i++) {
                  array[i] = nextInt();
              }
              return array;
          }
  
          long[] nextLongArray(int n) {
              long[] array = new long[n];
              for (int i = 0; i < n; i++) {
                  array[i] = nextLong();
              }
              return array;
          }
      }
  }