C语言做一个随机生成数组，数组排序，二分查找，增删改查的集成程序

Question

1.随机生成数组

2.数组排序

3.二分查找

4.增删改查

5.集成为一个C语言程序

Answer 1

# include <stdio.h>
binarySearch(int a[], int n, int key){
    int low = 0;
    int high = n - 1;
    while(low<= high){
        int mid = (low + high)/2;
        int midVal = a[mid];
        if(midVal<key)
            low = mid + 1;
        else if(midVal>key)
            high = mid - 1;
        else
            return mid;
    }
    return -1;
}
int main(void)
{
	int  val, ret;
	
    int a[] = {900, 2, 3, -58, 34, 76, 32, 43, 56, -70, 35, -234, 532, 543, 2500};
    int n;  //存放数组a中元素的个数
    int i;  //比较的轮数
    int j;  //每轮比较的次数
    int buf;  //交换数据时用于存放中间数据
    n = sizeof(a) / sizeof(a[0]);  /*a[0]是int型, 占4字节, 所以总的字节数除以4等于元素的个数*/
     printf("排序前的数组为：\n");
    for (i=0; i<n; ++i)
    {
        printf("%d\x20", a[i]);
    }
    printf("\n\n");
    for (i=0; i<n-1; ++i)  //比较n-1轮
    {
        for (j=0; j<n-1-i; ++j)  //每轮比较n-1-i次,
        {
            if (a[j] > a[j+1])
            {
                buf = a[j];
                a[j] = a[j+1];
                a[j+1] = buf;
            }
        }
    }
    printf("排序后的数组为：\n\n");
    for (i=0; i<n; ++i)
    {
        printf("%d\x20", a[i]);
    }
    printf("\n\n请输入要查找的数：");
    
    scanf("%d",&val);
    ret = binarySearch(a,20,val);
    if(-1 == ret)
        printf("查找失败，按任意键退出 \n");
    else
        printf ("查找成功 \n");
    
}