用递归函数实现二分查找

Question

设计一个递归算法，实现对顺序查找表ST中key为k的二分查找,，表的长度为n；算法头给定：int binsearch(stable *ST,int low,int high，int k)

Answer 1

根据k与表值的比较，递归进行二分查找

#include <stdio.h>
#define MAXSIZE 1000
typedef struct _stable
{
    int length;
    int data[MAXSIZE];
}stable;
int binsearch(stable *ST,int low,int high，int k)
{
    if(low > high)
        return -1;
    int mid = (low+high)/2;
    if(ST[mid]==k)
        return mid;
    if(ST[mid] >k)
        return binsearch(ST,low,mid-1,k);
    return binsearch(ST,mid+1,high,k);
}
int main()
{
    stable st;
    scanf("%d",&st.length);
    for(int i=0;i<st.length;i++)
        scanf("%d",&st.data[i]);
    int k;
    scanf("%d",&k);
    int idx = binsearch(&st,0,st.length-1,k);
    printf("%d",idx);
}