Chapter 7, Problem 1E

Explanation of Solution

Method “lastIndexOf()” to return the last index of an array:

//Definition of class

public class Text {

    //Definition of main method

    public static void main(String[] args)

    {

        //Create an array

        int[] arr = {74, 85, 102, 99, 101, 85, 56};

        //Call the method lastIndexOf()

        System.out.println(lastIndexOf(arr, 85));

    }

    //Definition of method lastIndexOf()

public static int lastIndexOf(int[] arr, int finValue)

    {

//Traverse the for loop till it reaches the length of the array

        for (int i = arr.length - 1; i >= 0; i--)

        {

            //Check whether a[i] equals to target

            if (arr[i] == finValue)

            {

                //Return the value of i

                return i;

            }

        }

        //Return the value of -1

        return -1;

    }

}

Explanation:

• Definition of method “lastIndexOf()”.
  • Traverse the “for” loop until it reaches the length.
    • Check whether “a[i] ”to “finValue”
      • Return the value of “i”.
    • Return “-1”.

Sample Output

Output:

5