二分算法模板

//数组a[]中有n个元素，已经按升序排序，待查找的元素X
template<class Type>
{
    int BinarySearch(Type a[],const Type& x,int n)
    {
        int left = 0;                                     //左边界
        int right = n-1;                                  //右边界
        while(left <= right)
        {
            int middle = (left+right)/2;                  //中点
            if (x == a[middle]) return middle;            //找到x，返回数组中的位置
            else if (x > a[middle]) left = midlde + 1;
            else right = middle - 1;
        }
        return -1;                                        //未找到x
    }
}

 

转载于:https://www.cnblogs.com/pshw/p/5132986.html