c语言代码练习3改进

#define _CRT_SECURE_NO_WARNINGS 1
#include <stdio.h>
int main()
{
    int x = 0;
    printf("请输入一个整数:");
    scanf("%d", &x);
    int arr[] = { 1,2,3,4,5,6,7,8,9 };
    int a = sizeof(arr) / sizeof(arr[0]); //计算元素个数
    int left = 0; //左下标
    int right = a - 1; //右下标
    while (left <= right)
    {
        int z = (left + right)/2;
        if (arr[z] > x)
        {
            right = z - 1;
        }
        else if (arr[z] < x)
        {
            left = z + 1;
        }
        else 
        {
            printf("你想的数字%d在数组中",x);
            break;
        }
    }
    if (left > right)
    {
        printf("输入超出范围或输入错误");
}
}