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.*;
  import java.util.*;
  import java.lang.*;
  
  public class other {
      public static void main(String[] args) {
          InputStream inputStream = System.in;
          OutputStream outputStream = System.out;
          if (System.getProperty("ONLINE_JUDGE") == null) {
              long startTime = System.currentTimeMillis();
              try {
                  sc = new InputReader(new FileInputStream("input.txt"));
                  out = new PrintWriter(new FileOutputStream("output.txt"));
                  pr = new PrintWriter(new FileOutputStream("error.txt"));
              } catch (Exception ignored) {
              }
              int t = 1;
              int tt = t;
              t = sc.nextInt();
              while (t-- > 0) {
                  solve();
              }
              long endTime = System.currentTimeMillis();
              System.out.println("Time: " + (endTime - startTime) / tt + " ms");
              out.flush();
              pr.flush();
  
          } else {
              sc = new InputReader(inputStream);
              out = new PrintWriter(outputStream);
              pr = new PrintWriter(outputStream);
              int t = 1;
              t = sc.nextInt();
              while (t-- > 0) {
                  solve();
              }
              out.flush();
          }
      }
  
      public static void solve() {
          int n = sc.nextInt();
          if (n == 1) {
              out.println("z");
          } else {
              String ans = "a".repeat(n / 2);
              if (1 == (n & 1))
                  ans += "bc"+"a".repeat(n / 2 - 1);
              else
                  ans += "b"+"a".repeat(n / 2 - 1);
              out.println(ans);
          }
      }
  
      /*******************************************************************/
      /*
       * Set Iterator Iterator value = set.iterator(); Displaying the values after
       * iterating through the iterator
       * System.out.println("The iterator values are: "); while (value.hasNext()) {
       * System.out.println(value.next()); }
       */
  
      /*
       * Map Iterator: for (Map.Entry<Integer, Integer> entry : map.entrySet()){
       * System.out.println("Key => " + entry.getKey() + ", Value => " +
       * entry.getValue());}
       */
  
      // pair sort
      // Arrays.sort(lap, new Comparator<Pair>() {
      // @Override
      // public int compare(Pair p1, Pair p2) {
      // return Integer.compare(p1.first, p2.first);
      // }
      // });
  
      // Globals
  
      public static int inf = Integer.MAX_VALUE;
      public static int minf = Integer.MIN_VALUE;
      public static int mod = 1000000007;
      public static int ml = (int) 1e9;
      public static InputReader sc;
      public static PrintWriter out;
      public static PrintWriter pr;
  
      // Pair
  
      static class Pair {
          int first, second;
  
          Pair(int x, int y) {
              this.first = x;
              this.second = y;
          }
      }
  
      // FastReader Class
  
      static class InputReader {
          public BufferedReader reader;
          public StringTokenizer tokenizer;
  
          public InputReader(InputStream stream) {
              reader = new BufferedReader(new InputStreamReader(stream), 32768);
              tokenizer = null;
          }
  
          public String next() {
              while (tokenizer == null || !tokenizer.hasMoreTokens()) {
                  try {
                      tokenizer = new StringTokenizer(reader.readLine());
                  } catch (IOException e) {
                      throw new RuntimeException(e);
                  }
              }
              return tokenizer.nextToken();
          }
  
          public int nextInt() {
              return Integer.parseInt(next());
          }
  
          public long nextLong() {
              return Long.parseLong(next());
          }
  
          public double nextDouble() {
              return Double.parseDouble(next());
          }
      }
  
      // Node class
  
      static class Node {
          Node next;
          int data;
  
          Node(int x) {
              next = null;
              this.data = x;
          }
      }
  
      // Tree class
  
      static class Tree {
          Tree left, right;
          int data;
  
          Tree(int x) {
              this.data = x;
              left = null;
              right = null;
          }
      }
  
      // Req Functions
  
      public static int gcd(int a, int b) {
          if (a == 0)
              return b;
          return gcd(b % a, a);
      }
  
      public static int lcm(int a, int b) {
          return (a / gcd(a, b)) * b;
      }
  
      public static long gcd(long a, long b) {
          if (a == 0)
              return b;
          return gcd(b % a, a);
      }
  
      public static long lcm(long a, long b) {
          return (a / gcd(a, b)) * b;
      }
  
      static long nCr(int n, int r) {
          return fact(n) / (fact(r) * fact(n - r));
      }
  
      static long fact(int n) {
          int res = 1;
          for (int i = 2; i <= n; i++)
              res = res * i;
          return res;
      }
  
      static long nCr(long n, long r) {
          return fact(n) / (fact(r) * fact(n - r));
      }
  
      static long fact(long n) {
          int res = 1;
          for (int i = 2; i <= n; i++)
              res = res * i;
          return res;
      }
  
      public static String reverseString(String input) {
          StringBuilder str = new StringBuilder("");
  
          for (int i = input.length() - 1; i >= 0; i--) {
              str.append(input.charAt(i));
          }
          return str.toString();
      }
  
      public static int maxOf3(int x, int y, int z) {
          return Math.max(x, Math.max(y, z));
      }
  
      public static int minof3(int x, int y, int z) {
          return Math.min(x, Math.min(y, z));
      }
  
      public static long maxOf3(long x, long y, long z) {
          return Math.max(x, Math.max(y, z));
      }
  
      public static long minof3(long x, long y, long z) {
          return Math.min(x, Math.min(y, z));
      }
  
      public static void arrInput(int[] arr, int n) {
          for (int i = 0; i < n; i++)
              arr[i] = sc.nextInt();
      }
  
      public static void arrInput(long[] arr, int n) {
          for (int i = 0; i < n; i++)
              arr[i] = sc.nextLong();
      }
  
      public static void arrInput(Pair[] pair, int n) {
          for (int i = 0; i < n; i++)
              pair[i] = new Pair(sc.nextInt(), sc.nextInt());
      }
  
      public static int lowerBound(int[] arr, int x) {
          int l = -1, r = arr.length;
          while (l + 1 < r) {
              int m = (l + r) >>> 1;
              if (arr[m] >= x)
                  r = m;
              else
                  l = m;
          }
          return r;
      }
  
      public static int upperBound(int[] arr, int x) {
          int l = -1, r = arr.length;
          while (l + 1 < r) {
              int m = (l + r) >>> 1;
              if (arr[m] <= x)
                  l = m;
              else
                  r = m;
          }
          return l + 1;
      }
  
      public static void fill(char[][] arr, char c) {
          int n = arr.length, m = arr[0].length;
          for (int i = 0; i < n; i++)
              for (int j = 0; j < m; j++)
                  arr[i][j] = c;
      }
  
      public static void fill(int[][] arr, int c) {
          int n = arr.length, m = arr[0].length;
          for (int i = 0; i < n; i++)
              for (int j = 0; j < m; j++)
                  arr[i][j] = c;
      }
  
      public static void fill(long[][] arr, long c) {
          int n = arr.length, m = arr[0].length;
          for (int i = 0; i < n; i++)
              for (int j = 0; j < m; j++)
                  arr[i][j] = c;
      }
  
      public static void merge(int arr[], int l, int m, int r) {
          int n1 = m - l + 1;
          int n2 = r - m;
          int L[] = new int[n1];
          int R[] = new int[n2];
          for (int i = 0; i < n1; ++i)
              L[i] = arr[l + i];
          for (int j = 0; j < n2; ++j)
              R[j] = arr[m + 1 + j];
          int i = 0, j = 0;
          int k = l;
          while (i < n1 && j < n2) {
              if (L[i] >= R[j]) {
                  arr[k] = L[i];
                  i++;
              } else {
                  arr[k] = R[j];
                  j++;
              }
              k++;
          }
          while (i < n1) {
              arr[k] = L[i];
              i++;
              k++;
          }
          while (j < n2) {
              arr[k] = R[j];
              j++;
              k++;
          }
      }
  
      public static void reversesort(int arr[], int l, int r) {
          if (l < r) {
              int m = l + (r - l) / 2;
              reversesort(arr, l, m);
              reversesort(arr, m + 1, r);
              merge(arr, l, m, r);
          }
      }
  
      public static void merge(long arr[], int l, int m, int r) {
          int n1 = m - l + 1;
          int n2 = r - m;
          long L[] = new long[n1];
          long R[] = new long[n2];
          for (int i = 0; i < n1; ++i)
              L[i] = arr[l + i];
          for (int j = 0; j < n2; ++j)
              R[j] = arr[m + 1 + j];
          int i = 0, j = 0;
          int k = l;
          while (i < n1 && j < n2) {
              if (L[i] >= R[j]) {
                  arr[k] = L[i];
                  i++;
              } else {
                  arr[k] = R[j];
                  j++;
              }
              k++;
          }
          while (i < n1) {
              arr[k] = L[i];
              i++;
              k++;
          }
          while (j < n2) {
              arr[k] = R[j];
              j++;
              k++;
          }
      }
  
      public static void reversesort(long arr[], int l, int r) {
          if (l < r) {
              int m = l + (r - l) / 2;
              reversesort(arr, l, m);
              reversesort(arr, m + 1, r);
              merge(arr, l, m, r);
          }
      }
  
      public static void sort(int[] arr) {
          Arrays.sort(arr);
      }
  
      public static void sort(long[] arr) {
          Arrays.sort(arr);
      }
  
      public static void sort(ArrayList<Integer> list) {
          Collections.sort(list);
      }
  
      public static long sumint(int n) {
          long ans = 0;
          char[] s = String.valueOf(n).toCharArray();
          for (int i = 0; i < s.length; ++i)
              ans += s[i] - '0';
          return ans;
      }
  
      public static long sumint(long n) {
          long ans = 0;
          char[] s = String.valueOf(n).toCharArray();
          for (int i = 0; i < s.length; ++i)
              ans += s[i] - '0';
          return ans;
      }
  
      // debug
  
      public static void debug() {
          if (sysFlag)
              pr.println("");
      }
  
      public static boolean sysFlag = System.getProperty("ONLINE_JUDGE") == null;
  
      public static void debug(int[][] dp) {
          if (sysFlag) {
              for (int i = 0; i < dp.length; ++i) {
                  pr.print(i + "--> ");
                  for (int j = 0; j < dp[0].length; ++j) {
                      pr.print(dp[i][j] + " ");
                  }
                  pr.println("");
              }
          }
      }
  
      public static void debug(char[][] arr) {
          if (sysFlag) {
              for (int i = 0; i < arr.length; ++i) {
                  for (int j = 0; j < arr[0].length; ++j) {
                      pr.print(arr[i][j]);
                  }
                  pr.println("");
              }
          }
      }
  
      public static void debug(long[][] dp) {
          if (sysFlag) {
              for (int i = 0; i < dp.length; ++i) {
                  pr.print(i + "--> ");
                  for (int j = 0; j < dp[0].length; ++j) {
                      pr.print(dp[i][j] + " ");
                  }
                  pr.println("");
              }
          }
      }
  
      public static void debug(int x) {
          if (sysFlag)
              pr.println("Int-Ele: " + x);
      }
  
      public static void debug(String x) {
          if (sysFlag)
              pr.println("String: " + x);
      }
  
      public static void debug(char x) {
          if (sysFlag)
              pr.println("Char: " + x);
      }
  
      public static void debug(long x) {
          if (sysFlag)
              pr.println("Long-Ele: " + x);
      }
  
      public static void debug(int[] arr) {
          if (sysFlag) {
              for (int i = 0; i < arr.length; ++i) {
                  pr.println(i + " -> " + arr[i]);
              }
          }
      }
  
      public static void debug(char[] arr) {
          if (sysFlag) {
              for (int i = 0; i < arr.length; ++i) {
                  pr.println(i + " -> " + arr[i]);
              }
          }
      }
  
      public static void debug(long[] arr) {
          if (sysFlag) {
              for (int i = 0; i < arr.length; ++i) {
                  pr.println(i + " -> " + arr[i]);
              }
          }
      }
  
      public static void debug(ArrayList<Integer> list) {
          if (sysFlag) {
              for (int i = 0; i < list.size(); ++i) {
                  pr.println(i + " -> " + list.get(i));
              }
          }
      }
  
      public static void Ldebug(ArrayList<Long> list) {
          if (sysFlag) {
              for (int i = 0; i < list.size(); ++i) {
                  pr.println(i + " -> " + list.get(i));
              }
          }
      }
  
      public static void debugmapII(HashMap<Integer, Integer> map) {
          if (sysFlag) {
              for (Map.Entry<Integer, Integer> entry : map.entrySet())
                  pr.println("Key => " + entry.getKey() + ", Value => " + entry.getValue());
          }
      }
  
      public static void debugmapLI(HashMap<Long, Integer> map) {
          if (sysFlag) {
              for (Map.Entry<Long, Integer> entry : map.entrySet())
                  pr.println("Key => " + entry.getKey() + ", Value => " + entry.getValue());
          }
      }
  
      public static void debugmapLL(HashMap<Long, Long> map) {
          if (sysFlag) {
              for (Map.Entry<Long, Long> entry : map.entrySet())
                  pr.println("Key => " + entry.getKey() + ", Value => " + entry.getValue());
          }
      }
  
      public static void debugmapIL(HashMap<Integer, Long> map) {
          if (sysFlag) {
              for (Map.Entry<Integer, Long> entry : map.entrySet())
                  pr.println("Key => " + entry.getKey() + ", Value => " + entry.getValue());
          }
      }
  
      public static void debugmapSL(HashMap<String, Long> map) {
          if (sysFlag) {
              for (Map.Entry<String, Long> entry : map.entrySet())
                  pr.println("Key => " + entry.getKey() + ", Value => " + entry.getValue());
          }
      }
  
      public static void debugmapCL(HashMap<Character, Long> map) {
          if (sysFlag) {
              for (Map.Entry<Character, Long> entry : map.entrySet())
                  pr.println("Key => " + entry.getKey() + ", Value => " + entry.getValue());
          }
      }
  
      public static void debugmapSI(HashMap<String, Integer> map) {
          if (sysFlag) {
              for (Map.Entry<String, Integer> entry : map.entrySet())
                  pr.println("Key => " + entry.getKey() + ", Value => " + entry.getValue());
          }
      }
  
      public static void debugmapCI(HashMap<Character, Integer> map) {
          if (sysFlag) {
              for (Map.Entry<Character, Integer> entry : map.entrySet())
                  pr.println("Key => " + entry.getKey() + ", Value => " + entry.getValue());
          }
      }
  
      public static void debug(Set<Integer> set) {
          if (sysFlag) {
              Iterator value = set.iterator();
              int i = 1;
              while (value.hasNext()) {
                  pr.println((i++) + "-> " + value.next());
              }
          }
      }
  
      public static void debug(Pair[] pair, int n) {
          if (sysFlag) {
              for (int i = 0; i < n; i++) {
                  pr.println("first:" + pair[i].first + " second:" + pair[i].second);
              }
          }
      }
  }
  