Question

norm [email protected] program11 even Positions prev I next chance Given an array of integer values, return a new array consisting only of the elements that have even- numbered indexes. even Positions([7, 51) [7] even Positions([8, 1, 7, 4, 6, 10, 5]) [8, 7, 6, 51 evenPositions([13]) [13] Save, Compile, Run Go int[1 even Positions(int[] nums) int[] newArrays new int[nums. length/2]; for (int i 0; iknums.length; it 2){ new Array[i] nums[ij;l if (nums. length 2- 1) newArray new int[ nums. length +1)/2] for (int i e; i nums. length; i+ 2){ newArray[i] nums [i]; return newArray;
Two questions, 1) how do I do this, 2) what is wrong with my code

Answer 1

Ques 1 : how to do?

Ans: The following function will do the work for you

int[] evenPositions(int[] nums)
   {
       int i,j,len;
       if(nums.length%2==0)
       {
           len=nums.length/2;
       }
       else
       {
           len = (nums.length+1)/2;
       }
       int[] newarray = new int[len];
       for(i=0,j=0;i<nums.length;i+=2,++j)
       {
           newarray[j]=nums[i];
       }
       return newarray;
   }

------

To solve your question you first need to know the length of your array to be returned. For that first check if the length of given array is even or odd. In case it is even then the length of newarray should be length/2 else length of newarray should be (length+1)/2.

A loop is started to copy the values. Here we skip odd values of given array and copy the rest.

Then newarray is returned.

output

Problems Javadoc e Declaration Console 3 <terminated> Even [Java Application C:Program Files Javalirel Tnitial Array 8 1 7 4 6 10 5 Result

This is the output I got when my main function was

public static void main(String[] args)
   {
       int[] array1 = {8,1,7,4,6,10,5};
       System.out.println("Initial Array");
       for(int i=0;i<array1.length;++i)
       {
           System.out.print(array1[i]+" ");
       }
      
       int[] result = evenPositions(array1);
       System.out.println("\nResult");
       for(int i=0;i<result.length;++i)
       {
           System.out.print(result[i]+" ");
       }
   }

Question 2 : What is wrong with the code given?

Answer : I found 2 wrong things in your code

First, the line int[] newArray = new int[nums.length];

When this line was written there was no check on whether nums.length is odd or even. This is not the main problem.

Second, This one is the main problem. In the code you have written newArray[i] = nums[i] which is wrong as we are not copying at odd positions in newArray. So, for example nums is {1,2,3,4,5,6}.

newArray[0] = nums[0] = 1

newArray[2] = nums[2] = 3

Here newArray[1] is not given any value and loops move forward and tries newArray[4] = nums[4] = 5 which is also an error as we have exceeded the size of array newArray.