package util;

class BinarySearch {

    static int binarySearch(int[] array,int goal){//传入排好序的数组和目标数字

        int low = 0;//数组的开始项

        int high = array.length - 1;//数组的结束项

        while(low <= high)

        {

            int middle = (low + high) / 2;//数组分割数

            if(goal == array[middle])

            {

                return middle;

            }

            if(goal > array[middle])

            {

                low = middle + 1;

            }

            if(goal < array[middle])

            {

                high = middle - 1;

            }

        }

        return -1;

    }

}