几种排序算法 C++

#include <vector>
using namespace std;

class SortAlgorithm
{
public:
SortAlgorithm(int = 10);
void displayVector();
void swap(int &, int &);

void insertSort();                     //O(n^2)
void selectSort();                    //O(n^2)
void mergeSort();                    //O(n log n)
void bubbleSort();                  //O(n^2)
void quickSort(  int , int  );     //worst: O(n^2),  best: O(n log n)

int partition( int , int  );
void sortSubVector(int , int );
void merge(int , int , int , int );
private:
int size;
vector< int > source;
vector< int > temp;

};

#include <iostream>
#include <cstdlib> // prototypes for functions srand and rand
#include <ctime> // prototype for function time
#include <algorithm> // prototype for sort function
#include "SortAlgorithm.h" // class BinarySearch definition
using namespace std;

SortAlgorithm::SortAlgorithm(int vectorSize)
{
size = ( vectorSize > 0 ? vectorSize : 10 ); // validate vectorSize
srand( time( 0 ) ); // seed using current time

// fill vector with random ints in range 10-99
for ( int i = 0; i < size; i++ )
source.push_back( 10 + rand() % 90 ); // 10-99

temp = source;
}

void SortAlgorithm::insertSort()
{
int insert;
for(int next = 1; next < size; next++){
insert = temp[next];
int moveItem = next;

while((moveItem > 0) && (temp[moveItem - 1] > insert)){
temp[moveItem] = temp[moveItem - 1];
moveItem--;
}

temp[moveItem] = insert;
}
}

void SortAlgorithm::selectSort()
{
int loop = size - 1;
int smallest;

for(int i = 0; i < loop; i++){
smallest = i;

for(int j = i + 1; j < size; j++){
if(temp[j] < temp[smallest])
smallest = j;
}

swap(temp[i], temp[smallest]);
}
}

void SortAlgorithm::mergeSort()
{
sortSubVector(0, size - 1);
}

void SortAlgorithm::bubbleSort()
{
int comp; // used to control for loop and for subscripts
bool swapCheck = true; // was a swap made?

for ( int pass = 1; pass < size && swapCheck; pass++ ) {
swapCheck = false; // assume no swaps will be made

// traverse and compare unsorted part of vector
for ( comp = 0; comp < size - pass; comp++ ){

// compare adjacent vector elements
if ( temp[ comp ] > temp[ comp + 1 ] ) {
swap(temp[comp], temp[comp + 1]);
swapCheck = true;
} // end if

} // end inner for
} // end outer for
}

void SortAlgorithm::quickSort(int first, int last )
{
int currentLocation;

if ( first >= last )
return;

currentLocation = partition( first, last ); // place an element
quickSort( first, currentLocation - 1 ); // sort left side
quickSort( currentLocation + 1, last ); // sort right side
} // end function quickSortHelper

// partition the vector into multiple sections
int SortAlgorithm::partition( int left, int right )
{
int position = left;

// loop through the portion of the vector
while ( true )
{
//first: from right ro left
while ( temp[ position ] <= temp[ right ] && position != right )
--right;

if ( position == right )
return position;

if ( temp[ position ] > temp[ right ])
{
swap( temp[ position ], temp[ right ] );
position = right;
} // end if
//second: from left to right
while ( temp[ left ] <= temp[ position ] && left != position )
++left;

if ( position == left )
return position;

if ( temp[ left ] > temp[ position ] )
{
swap( temp[ position ], temp[ left ] );
position = left;
} // end if
} // end while
} // end function partition

void SortAlgorithm::sortSubVector(int low, int high)
{
if((high - low) >= 1){
int middle1 = (low + high) / 2;
int middle2 = middle1 + 1;

/*cout << "split:   ";
displaySubVector(low, high);
cout << endl << "       ";
displaySubVector(low, middle1);
cout << endl << "       ";
displaySubVector(middle2, high);
cout << endl << endl;*/

sortSubVector(low, middle1);
//cout << "Stop here1. low = " << low << ", middle1 = " << middle1 << endl;
sortSubVector(middle2, high);
//cout << "Stop here2. middle2 = " << middle2 << ", high = " << high << endl;

merge(low, middle1, middle2, high);

}
}

void SortAlgorithm::merge(int left, int middle1, int middle2, int right)
{
int leftIndex = left;
int rightIndex = middle2;
int combinedIndex = left;
vector<int> combined(size);

/*cout << "merge:   ";
displaySubVector(left, middle1);
cout << endl << "       ";
displaySubVector(middle2, right);
cout << endl;*/

while(leftIndex <= middle1 && rightIndex <= right){
if(temp[leftIndex] <= temp[rightIndex])
combined[combinedIndex++] = temp[leftIndex++];
else
combined[combinedIndex++] = temp[rightIndex++];
}

if(leftIndex == middle2){
while(rightIndex <= right)
combined[combinedIndex++] = temp[rightIndex++];
}
else{
while(leftIndex <= middle1)
combined[combinedIndex++] = temp[leftIndex++];
}

for(int i = left; i <= right; i++)
temp[i] = combined[i];

/*cout << "       ";
displaySubVector(left, right);
cout << endl << endl;*/
}

void SortAlgorithm::swap(int &x, int &y)
{
int t;

t = x;
x = y;
y = t;
}

void SortAlgorithm::displayVector()
{
for(int i = 0; i < size; i++){
cout << " " << temp[i];
if((i + 1) % 10 == 0)
cout << endl;
}

cout << endl;

temp = source;
}

#include <iostream>
#include "SortAlgorithm.h" // class BinarySearch definition
#include "BucketSort.h"
using namespace std;

int main()
{
int num;
cout << "Please input the integer number you want to sort:  ";
cin >> num;

SortAlgorithm sortVector(num);
cout << "Unsort elements: \n";
sortVector.displayVector();

sortVector.insertSort();
cout << "\nInsert sorted elements: \n";
sortVector.displayVector();

sortVector.selectSort();
cout << "\nSelect sorted elements: \n";
sortVector.displayVector();

sortVector.mergeSort();
cout << "\nMerge sorted elements: \n";
sortVector.displayVector();

sortVector.bubbleSort();
cout << "\nBubble sorted elements: \n";
sortVector.displayVector();

sortVector.quickSort(0, num - 1);
cout << "\nQuick sorted elements: \n";
sortVector.displayVector();

/*BucketSort bucketSortVector( num ); // create BucketSort object

cout << "Vector elements in original order:\n";
bucketSortVector.displayElements();

bucketSortVector.sort(); // sort the vector

cout << "\nVector elements in sorted order:\n";
bucketSortVector.displayElements();*/
}