我的第35个代码

创建函数利用二分法

#define  _CRT_SECURE_NO_WARNINGS 1#include<stdio.h>#include<math.h>#include<string.h>int judge(int arr[], int k,int length){    int left = 1;    int right = length;    while (left<=right)    {        int mid = (right + left) / 2;        if (arr[mid - 1] < k)        {            left = mid + 1;        }        else if (arr[mid - 1 > k])        {            right = mid - 1;        }        else if (arr[mid - 1] == k)            return mid - 1;     }    return -1;}int main(){    char arr[] = { 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 };    int length = strlen(arr);    int x = 0;    printf("请输入1-10内您想查找的数字\n");    scanf("%d", &x);    int ret = judge(arr, x,length);    if (ret == -1)    {        printf("找不到这个数字\n");    }    else    {        printf("找到了，下标是%d\n", x -1);    }    return 0;}