SortAlgorithm.h
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;
};
</div>
SortAlgorithm.cpp
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: ";
displaySubVect