public class BinarySearch {

    // constructor
    public BinarySearch(){
    }

    // input:  array of numbers, and a target to search for
    // output: -1 if target is not found, else
    //          i such that numbers[i] = target
    public int search( int[] numbers, int target ){
	int start = 0;
	int end = numbers.length-1;
	while (start <= end){
	    int middle = (end + start)/2;
	    if (target == numbers[middle]){
		return middle;
	    }
	    else if (target > numbers[middle]){
		start = middle + 1;
	    }
	    else {
		end = middle - 1;
	    }
	}
	return -1;
    }

}