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Corrected some formatting error

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This commit is contained in:
mohit
2020-06-27 16:15:39 +05:30
parent c3c705b7c9
commit c0c8164dc8
1 changed files with 22 additions and 15 deletions
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37
sorting/quick_sort_3.cpp
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@@ -1,10 +1,10 @@
/*
Author: immortal-j
Implementation Details
Quick sort 3 works on Dutch National Flag Algorithm
The major diffrence between simple quicksort and quick sort 3 comes in the
function partition3 In quick_sort_partition3 we divide the vector/array into 3
parts. quick sort 3 works faster in some cases as compared to simple quicksort.
*Author: immortal-j
*Implementation Details
*Quick sort 3 works on Dutch National Flag Algorithm
*The major diffrence between simple quicksort and quick sort 3 comes in the
*function partition3 In quick_sort_partition3 we divide the vector/array into 3
*parts. quick sort 3 works faster in some cases as compared to simple quicksort.
*/
#include <iostream>
// function to swap elements
@@ -16,20 +16,23 @@ void swap(int *a, int *b) {
// function to print an array
void print_arr(int arr[], int n) {
for (int i = 0; i < n; ++i)
for (int i = 0; i < n; ++i){
std::cout << arr[i] << " ";
}
std::cout << "\n";
}
/* This function partitions arr[] in three parts
a) arr[l..i] contains all elements smaller than pivot
b) arr[i+1..j-1] contains all occurrences of pivot
c) arr[j..r] contains all elements greater than pivot */
*a) arr[l..i] contains all elements smaller than pivot
*b) arr[i+1..j-1] contains all occurrences of pivot
*c) arr[j..r] contains all elements greater than pivot
*/
void partition3(int arr[], int low, int high, int *i, int *j) {
// To handle 2 elements
if (high - low <= 1) {
if (arr[high] < arr[low])
if (arr[high] < arr[low]){
swap(&arr[high], &arr[low]);
}
*i = low;
*j = high;
return;
@@ -38,12 +41,15 @@ void partition3(int arr[], int low, int high, int *i, int *j) {
int mid = low;
int pivot = arr[high];
while (mid <= high) {
if (arr[mid] < pivot)
if (arr[mid] < pivot){
swap(&arr[low++], &arr[mid++]);
else if (arr[mid] == pivot)
}
else if (arr[mid] == pivot){
mid++;
else if (arr[mid] > pivot)
}
else if (arr[mid] > pivot){
swap(&arr[mid], &arr[high--]);
}
}
// update i and j
@@ -53,8 +59,9 @@ void partition3(int arr[], int low, int high, int *i, int *j) {
// 3-way partition based quick sort
void quicksort(int arr[], int low, int high) {
if (low >= high) // 1 or 0 elements
if (low >= high){ // 1 or 0 elements
return;
}
int i, j;