bin_search.cpp

C++的电子教程

#include <stdio.h>
#define Max 100
int a[Max],n,v;

//二分查找
int bin_search(int a[],int n,int v)
{
	int low=0,high=n-1,mid;
	while (low<high)
	{
		mid=int((low+high)/2);
		if (v==a[mid]) return mid;
		if (v<a[mid])  high=mid-1;
		else           low=mid+1;
	}
	return -1;
}


//主函数
void main()
{
	n=10;
	int r,i;
	for (i=0;i<n;i++)
	{
		printf("输入第%d个元素值",i);
		scanf("%d",&a[i]);
	}
	printf("原数组为：");
	for (i=0;i<n;i++)
	printf("%3d,",a[i]);
	printf("\n");
    printf("待查找的值v：");
	scanf("%d",&v);
    r=bin_search(a,n,v);
	if (r>0)
		printf("查找成功，为第%3d个元素。",r+1);
	else
		printf("查找失败!");
}