排序算法实现大全
后面的例程,都是对数组的排序,使用静态链表的也适用于链表的排序。为简单起见,只对单关键码排序,并且最后的结果都是从头到尾按升序排列。下面是统一的测试程序:#include #include using namespace std;#include #include #include #include "InsertSort.h"#define random(num) (rand() % (num))#define randomize() srand((unsigned)time(NULL))#define N 10000 //排序元素的数目#define SORT InsertSort //排序方法class timer//单位ms{public:void start() { start_t = clock(); }clock_t time() { return (clock() - start_t); }private:clock_t start_t;};int KCN, RMN; timer TIMER;void test(int a[]){TIMER.start();SORT(a, N, KCN, RMN);cout << "\tTimeSpared: " << TIMER.time() << "ms" << endl;cout << "KCN=" << left << setw(11) << KCN; cout << "KCN/N=" << left << setw(11)<< (double)KCN/N;cout << "KCN/N^2=" << left << setw(11)<< (double)KCN/N/N;cout << "KCN/NlogN=" << left << setw(11)<< (double)KCN/N/log((double)N)*log(2.0) << endl;cout << "RMN=" << left << setw(11) << RMN;cout << "RMN/N=" << left << setw(11)<< (double)RMN/N;cout << "RMN/N^2=" << left << setw(11)<< (double)RMN/N/N;cout << "RMN/NlogN=" << left << setw(11)<< (double)RMN/N/log((double)N)*log(2.0) << endl;}int main(){int i;//randomize();为了在相同情况下比较各个排序算法,不加这句int* ascending = new int[N];//升序序列int* descending = new int[N];//降序序列int* randomness = new int[N];//随机序列for (i = 0; i < N; i++) { ascending[i] = i; randomness[i] = i; descending[i] = N - i - 1;}for (i = 0; i < N; i++) swap(randomness[i], randomness[random(N)]);cout << "Sort ascending N=" << N; test(ascending);cout << "Sort randomness N=" << N; test(randomness);cout << "Sort descending N=" << N; test(descending);return 0;}
需要说明一点,KCN(关键码比较次数)、RMN(记录移动次数)并不是算法必须的,是为了对算法的性能有个直观的评价(不用那些公式算来算去)。对10000个整数排序应该是最省事的测试手段,建议不要再增多记录数目了,一是在最坏的情况不用等太久的时间,二是避免KCN、RMN溢出,另外有些递归的算法在情况比较糟的时候,记录数目太多堆栈可能会溢出,导致程序崩溃。插入排序
基本思想是,每步将一个待排序的记录,按其关键码大小,插入到前面已经排好序的记录的适当位置,从头做到尾就可以了。
直接插入排序
template void InsertSort(T a[], int N, int& KCN, int& RMN){KCN = 0; RMN = 0;for (int i = 1;