希尔排序（C++模版技术实现）

下面代码仅供本人复习数据结构所用，实用性N低，各位飘过吧~~哈哈:>

//
// C++模版技术实现希尔排序. 
// 
 
#include <cstdlib>
#include <cstring>
#include <iostream> 
#include <stdexcept>
 
 
//
// 希尔排序函数模版. 
//
template <typename T>
void shellSort(T *array, const size_t first, const size_t last)
{
    if (NULL == array || first >= last) {
        throw std::invalid_argument("希尔排序参数错误!");
    }
     
    const size_t LENGTH = last - first + 1;
    size_t gap = LENGTH, i, j;
    T temp;
     
    do {
        gap = gap / 3 + 1;
        //
        // 内层循环是直接插入排序，只是各相邻排序元素间隔为 gap. 
        //
        for (i = gap; i < LENGTH; i += gap)
        {
            temp = array[i];
            for (j = i; j >= gap && temp < array[j - gap]; j -= gap)
            { 
                array[j] = array[j - gap];
            }
            if (j >= 0) {
                array[j] = temp;
            }
        }
    } while (gap > 0);
}
 
//
// 测试.
//
int main(void)
{
    char szTest[] = "Shell sort algorithm test case !"; 
    int iarrTest[] = {23, 12, 2, 123, 72, 35, 49, 51, 83, 94, 65}; 
    const size_t INT_ARR_SIZE = sizeof(iarrTest) / sizeof(iarrTest[0]);
 
    shellSort(szTest, 0, strlen(szTest) - 1);
    shellSort(iarrTest, 0, INT_ARR_SIZE - 1);
     
    std::cout << szTest << std::endl;
 
    for (size_t i = 0; i < INT_ARR_SIZE; ++i)
    {
        std::cout << iarrTest[i] << " "; 
    }
    std::cout << std::endl;
 
    return EXIT_SUCCESS; 
}