DSA by Brendan Yu Soon

mergesort

1171100342 — 2020-09-01 01:47:29 UTC

#include
using namespace std;

typedef int DataType;
const int N_ITEMS = 10;

void displayArray( const DataType[], int, int );
void merge( DataType[], int, int, int );
void mergeSort( DataType[], int, int );

int main(){
DataType a[ N_ITEMS ] = { 10, 5, 21, 5, 99, 8, 16, 4, 72, 25 };

cout << "Initial array : ";
displayArray( a, 0, N_ITEMS - 1 );
cout << endl;

mergeSort( a, 0, N_ITEMS - 1 );

cout << "Sorted array : ";
displayArray( a, 0, N_ITEMS - 1 );
cout << endl;

return 0;
}

void displayArray( const DataType theArray[], int first, int last ){
for ( int i = first; i <= last; ++i )
cout << theArray[ i ] << " ";
}

void merge(DataType theArray[], int first, int mid, int last ){
//To do: Merge two halves into a sorted part using a
// temporary array
}

void mergeSort(DataType theArray[], int first, int last){
//To do: Recursively call the mergeSort to split then use
// the merge function to combine and sort the halves
}

quicksort

1171100342 — 2020-09-01 01:47:45 UTC

#include #include using namespace std; typedef int DataType; const int N_ITEMS = 10; void swap( DataType&, DataType& ); void displayArray( const DataType[], int, int ); void quickSort(DataType[], int, int); void partition(DataType[], int, int, int&); int main(){ DataType a[ N_ITEMS ] = { 10, 5, 21, 5, 99, 8, 16, 4, 72, 25 }; cout << "Initial array : "; displayArray( a, 0, N_ITEMS - 1 ); cout << endl; quickSort( a, 0, N_ITEMS - 1 ); cout << "Sorted array : "; displayArray( a, 0, N_ITEMS - 1 ); cout << endl; return 0; } void swap(DataType& x, DataType& y){ DataType temp = x; x = y; y = temp; cout << "Swapped " << setw(2) << x << " with " << setw(2) << y << " --->"; } void displayArray( const DataType theArray[], int first, int last ){ for ( int i = first; i <= last; ++i ) cout << setw(2) << theArray[ i ] << " "; } void partition(DataType theArray[], int first, int last, int& pivotIndex){ //To do: partition array into [ S1 | Pivot | S2 ] //set pivot to first element //sort unknowns to S1 and S2 //given items in S1 are < pivot // items in S2 are >= pivot } void quickSort(DataType theArray[], int first, int last){ //To do: implement quicksort when items in list > 1 }

radixsort

1171100342 — 2020-09-01 01:48:01 UTC

#include #include //stringstream using namespace std; typedef int DataType; const int N_ITEMS = 10; const int length = 2; void radixSort(string[], int, int ); void displayArray( const DataType[], int, int ); int main(){ DataType a[ N_ITEMS ] = { 10, 5, 21, 5, 99, 8, 16, 4, 72, 25 }; string s[ N_ITEMS ]; cout << "Initial array : "; displayArray( a, 0, N_ITEMS - 1 ); cout << endl; // Convert each element to string for ( int i = 0; i < N_ITEMS; i++ ){ stringstream ss; ss << a[i]; s[i] = ss.str(); for(int j=s[i].length(); j> a[i]; } cout << "Sorted array : "; displayArray( a, 0, N_ITEMS - 1 ); cout << endl; return 0; } void displayArray( const DataType theArray[], int first, int last ){ for ( int i = first; i <= last; ++i ) cout << theArray[ i ] << " "; } void radixSort(string theArray[], int size, int length){ //To do: radix sort by sorting from lowest power to highest }