CODEWITHSUNDEEP
javacollections
benz
benz

Reputation: 4629

Arrays search method confusion

I am confused about Arrays.binarySearch(Object[], Object).

public class SearchObjArray {

    public  static void main(String[] args){

        String[] sa = {"one","two","three","four"};

        Arrays.sort(sa);

        for(String s : sa ){
            System.out.println(s + " ");
        }
        System.out.println("\n one = " + Arrays.binarySearch(sa,"thro"));
}
}

When the program is run, it returns position -4. I was reading in the book, it states that, insertion point is represented as (-(insertionPoint)-1). Why it is like this? I am not able to grasp this point.

Upvotes: 0

Views: 34

Answers (1)

user1907906
user1907906

Reputation:

The insertion point is defined as the point at which the key would be inserted into the array.

{"one","two","three","four"}

sorted is 

{"four", "one", "three", "two"}

and throw comes after three. So the insertion point would be 3. The result thus is 

(-(insertionPoint) -1) =
(-(3)              -1) =
-4

Upvotes: 5

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