Question

Please write where its written write your code here!! please use java for the code! please use the given code and I will rate thanks

Magic index in an array a[1..n] is defined to be an index such that a[ i ] = i. Given an array of integers, write a recursive method to find the first magic index from left to right. If one exists in the given array, return the index number i, otherwise return -1.

Here are some test cases. The first number is the size of the array.

Input1

6

-2 -2 3 -2 -2 -1

Output1

-1

-------------------------------------------

Input2

5

-1 7 2 3 4

Output2

2

///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////

Code

import java.util.*;
import java.lang.*;
import java.io.*;
//Your program will be evaluated by this DriverMain class and several test cases.

public class DriverMain {
    public static void main(String[] args) {
        Scanner s = new Scanner(System.in);
        int N = s.nextInt();
        int A[] = new int[N];
        for (int i = 0; i < N; i++) {
            A[i] = s.nextInt();
        }
        ProblemSolution problemSolution = new ProblemSolution();
        System.out.print(problemSolution.findMagicIndex(A, N));
    }
}

import java.util.*;
import java.lang.*;
import java.io.*;

class ProblemSolution{
    public static int findMagicIndex(int[] a, int n){
        //write your code here
      
   }
}

Answer 1

class ProblemSolution{
public static int findMagicIndex(int[] a, int n){
if (n==0)
return -1;
if (a[a.length-n]==a.length-n)
return a.length-n;
return findMagicIndex( a, n-1);
}
}