C语言实现二分查找

#include<stdio.h>
int binary(int a[],int n,int target);//二分查找 
int main(void){
	int a[10]={11,12,13,14,15,16,17,18,19,20};
	int n=sizeof(a)/sizeof(a[0]);
	int target;
	scanf("%d",&target); 
	if(binary(a,n,target)!=-1){
		printf("查找的元素下标为：%d",binary(a,n,target));
	}else{
		printf("没有找到元素！"); 
	}
	return 0;
}
int binary(int a[],int n,int target){
	int low,high,mid;
	low=0;
	high=n-1;
	while(low<=high){
		int mid=(low+high)/2;
		if(a[mid]>target){
			high=mid-1;
		}else if(a[mid]<target){
			low=mid+1;
		}else{
			return mid;
		}
	}
	if(low>high){
		return -1;
	}
}