二分搜索

以为很麻烦，得调试一下，没想到这也太简单了????

public class BinarySearch {

    public int search(int[] nums, int target) {

        int i = 0;
        int j = nums.length-1;
        int mid;

        while(i <= j){

            mid = (i+j)/2;
            if(nums[mid] == target){
                return mid;
            }

            if(nums[mid] < target){
                i = mid + 1;
            }else {
                j = mid - 1;
            }

        }
        return -1;
    }

    public static void main(String[] args) {
        BinarySearch binarySearch = new BinarySearch();
        System.out.println(binarySearch.search(new int[]{-1,0,3,5,9,12}, 9));
    }
}