Question

Now this: Suppose that you have been assigned to take over a project from another programmer who has just been dismissed for writing buggy code. One of the methods you have been asked to rewrite has the following comment and prototype: /* Method: insertValue(value, array) / • Inserts a new value into a sorted array of integers by * creating a new array that is one element larger than the - original array and then copying the old elements into the • new array, inserting the specified value at its proper . position. * @param value The value to be inserted into the array + @param array An array sorted in ascending order • ereturn A newly allocated array with value inserted in order private int[] insertValue(int value, int[] array) { int( result = new int array length + 1]; for (int i = 0; i < result.length; i++) { result[i] = array[i]; int pos - 0; for (int i = 0; i < array.length; i++) { if (value > array[i]) { pos - i; break; for (int i - result.length; i >- pos; 1--) { result[i] = result[i-1]; result[pos] - value; return result; Unfortunately, the code contains several bugs. Circle the bugs in the implementation and write a short sentence explaining the precise nature of each problem you identify.

Answer 1

The bugs have been pointed out inline in the given code snippet:

    private int[] insertValue(int value, int[] array) {
       int[] result = new int[array.length + 1];
       /*
       * Bug #1: result.length will be 1 larger than array.length
       * hence, array[i] will throw indexOutOfBound exception
       * when it tries to access the element array[result.length]
       * The for-loop should run array.length times.
       */
       for (int i = 0 ; i < result.length; i++) {
           result[i] = array[i];
       }
      
       int pos = 0;
       /*
       * Here we are trying to find the position for the new value
       * Bug #2: if value > array[i], we need to keep the value
       * right after the position i, hence its position should be
       * i+1 and not i as written in line #26
       */
       for (int i = 0; i < array.length; i++) {
           if (value > array[i]) {
               pos = i;
               /*
               * Bug #3: break is not required here, because
               * it will cause the loop to exit at the very first
               * finding of value being greater than the element.
               * We need to keep traversing till we find the
               * immediate smaller number.
               */
               break;
           }
       }
       /*
       * Bug #4: Loop can't start with the result.length index.
       * as arrays indexing start with 0, hence i should start
       * with result.length - 1.
       *
       * Bug #5: If pos = 0, and i = 0 at some iteration,
       * the condition i>=pos will be true, and the loop will
       * execute making result[i-1] throw indexOutOfBounds
       * exception
       */
       for (int i = result.length; i >= pos; i--) {
           result[i] = result[i - 1];
       }

       result[pos] = value;
      
       return result;
   }
   

private int[] insertValue(int value, int[] array) { int[] result = new int[array.length + 1]; Bug #1: result.length will be 1 larger than array.length * hence, array[i] will throw indexOutOfBound exception * when it tries to access the element array[result.length] * The for-loop should run array.length times. for (int i = ; i< result.length; i++) { result[i] = array[i]; int pos = 0; * Here we are trying to find the position for the new value * Bug #2: if value > array[i], we need to keep the value * right after the position i, hence its position should be * i+l and not i as written in line #26 */ for (int i = 0; i < array.length; i++) { if (value > array[i]) { pos = i; * Bug #3: break is not required here, because * it will cause the loop to exit at the very first * finding of value being greater than the element. * We need to keep traversing till we find the * immediate smaller number. */ break; * Bug #4: Loop can't start with the result. length index. * as arrays indexing start with o, hence i should start * with result. length - 1. * Bug#5: If pos = 0, and i = at some iteration, * the condition i>=pos will be true, and the loop will * execute making result[i-1] throw indexOutOfBounds * exception for (int i = result.length; i >= pos; i--) { result[i] = result[i - 1]; result[pos] = value; return result;