c++——选择排序

 1 #include <iostream>
 2 
 3 #include "SortTestHelper.h"
 4 
 5 using namespace std;
 6 
 7 template<typename T>
 8 void selectionSort(T arr[],int n){
 9     for(int i = 0 ; i < n ; i ++){
10         int minIndex = i;
11         for( int j = i + 1 ; j < n ; j ++ )
12             if( arr[j] < arr[minIndex] )
13                 minIndex = j;
14         swap( arr[i] , arr[minIndex] );
15     }    
16 }
17 
18 int main(){
19     int n = 100000;
20     int *arr = SortTestHelper::generateRandomArray(n,0,n);
21     //selectionSort(arr,n);
22     //SortTestHelper::printArray(arr,n);
23     SortTestHelper::testSort("Selection Sort",selectionSort,arr,n);
24     delete[] arr;
25     return 0;
26 }

 1 #include <iostream>
 2 #include <ctime>
 3 #include <cassert>
 4 #include <string>
 5 
 6 using namespace std;
 7 
 8 namespace SortTestHelper{
 9     int *generateRandomArray(int n,int rangeL,int rangeR){
10         assert(rangeL <= rangeR);
11         int *arr = new int[n];
12         srand(time(NULL));
13         for(int i = 0 ; i < n ; i++)
14             arr[i] = rand()%(rangeR-rangeL+1) + rangeL;
15         return arr;
16     }
17     
18     template<typename T>
19     void printArray(T arr[],int n){
20         for(int i = 0;i<n;i++)
21             cout << arr[i] <<" ";
22         cout << endl;
23         return;
24     }
25     
26     template<typename T>
27     bool isSorted(T arr[],int n){
28         for(int i = 0 ; i<n-1 ; i++)
29             if(arr[i] > arr[i+1])
30                 return false;
31             return true;
32     }
33     template<typename T>
34     void testSort(const string &sortName,void (*sort)(T[],int),T arr[],int n){
35         
36         clock_t startTime = clock();
37         sort(arr,n);
38         clock_t endTime = clock();
39         
40         assert(isSorted(arr,n));
41         cout << sortName << " : " << double(endTime-startTime)/CLOCKS_PER_SEC << " s" <<endl;
42         
43         return;
44     }
45 }