折半查找

public class ZheBan {

    public static void main(String[] args) {         int[] nums = {1, 2, 3, 4, 5, 7};         System.out.println("二分/折半查找到所在的数组下标:\n" + find(nums, 5));

       //find (expr1,expr2)expr2不能超过数组的最后一个数组下标值     }

    private static int find(int[] nums, int findNum) {         int low = 0;         int high = nums.length;

        while (low <= high) {

            int mid = (low + high) / 2;

            if (nums[mid] == findNum) {                 return mid;             } else if (nums[mid] > findNum) {                 high = mid - 1;             } else if (nums[mid] < findNum) {                 low = mid + 1;             } else {                 return -1;             }         }         return -1;     } }