C++二分查找示例

/*
    二分查找示例示例 -- 只适合已排序数组
    Wirtten by: nick
    Date: 2012-10-16 12:13
*/

#include <iostream>
#include <iomanip>

using namespace std;


bool binarySearch(int list[], int end, int target, int& index);

int main()
{
    int a[10] = {0,1,2,3,4,5,6,7,8,9};  //已排序数组

    int ans=0;
    if(binarySearch(a, 9, 6, ans))
        cout << "Find! index = " << ans;

    return 0;
}

bool binarySearch(int list[], int end, int target, int& index)
{
    int first = 0;
    int last = end;
    int mid;
    while(first<=last)
    {
        mid = (first + last) / 2;
        if(target < list[mid])
            last = mid - 1;
        else if(target > list[mid])
            first = mid + 1;
        else
        {
            index = mid;
            break;
        }
    }
    return (list[mid] == target);
}
posted @ 2012-10-16 14:55  wouldguan  阅读(346)  评论(0编辑  收藏  举报