写代码可以在整型有序数组中查找想要的数字，找到了返回下标，找不到返回-1.（折半查找）

例如在这里查找数字6

#define _CRT_SECURE_NO_WARNINGS
#include <stdio.h>
#include <stdlib.h>
int my_search(int arr[], int key, int left, int right)
{
	while (left <=right)
	{
		int mid = left + (right-left) / 2;
		if (key <arr[mid])
		{
			right = mid - 1;
		}
		else if (key  > arr[mid])
		{
			left = mid + 1;
		}
		else
		{
			return mid;
		}

	}
	return -1;
}
int main()
{
	int key = 6;
	int arr[10] = { 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 };
	int ret =my_search(arr, key, 0, 9);
	if (ret == -1)
	{
		printf("没找到\n");
	}
	else 
	{
		printf("%d\n",ret);
	}
	system("pause");
	return 0;

}