Recursive Binary Search Array out of Index

Question

public static void main(String[] args) {
    int [] arr = {11,14,18,22,36,89,125};
    System.out.println(recursive_binary_search(arr,0,arr.length,989));

}


public static int recursive_binary_search(int[] A,int p,int r,int x) {

    if( p > r) {

        return -1;
    }else {
        int q=(p+r)/2;
        if(A[q]==x) {

            return q;
        }else if(A[q]>x) {

            return recursive_binary_search(A,p,q-1,x);
        }else {
            return recursive_binary_search(A,q+1,r,x);

        }


    }


}

Hey, thank you for reading. I am having some problem with this recursive binary search method. When I try to search something that is not in the array, java give me "Exception in thread "main" java.lang.ArrayIndexOutOfBoundsException: 7".

I thought it should return -1 because of the p>r condition. I tried to change the condition to p>=r but then it would return -1 for things that are actually present in array. What am I doing wrong? Thank you so much

Praveen · Accepted Answer · 2018-08-11 23:51:10Z

1

Your search should start with 0 to arr.length-1,

System.out.println(recursive_binary_search(arr,0,arr.length-1,989));

answered Aug 11, 2018 at 23:51

Praveen

1,8913 gold badges21 silver badges36 bronze badges

Sign up to request clarification or add additional context in comments.

Collectives™ on Stack Overflow

Recursive Binary Search Array out of Index

1 Answer 1

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

Comments

Your Answer

Sign up or log in

Post as a guest

Related