Update README.md with quick sort details

Author: samuelselasi

README.md

@@ -63,7 +63,6 @@ void print_array(const int *array, size_t size)
     printf("\n");
 }
 ```
-
 ```
 #include <stdio.h>
 #include "sort.h"
@@ -136,7 +135,7 @@ Write a function that sorts an array of integers in ascending order using the [B
 	* Prototype: `void bubble_sort(int *array, size_t size);`
 	* You’re expected to print the array after each time you swap two elements (See example below)
 
-* Write in the file `0-O`, the big O notations of the time complexity of the `Bubble sort` algorithm, with `1` notation per line:
+Write in the file `0-O`, the big O notations of the time complexity of the `Bubble sort` algorithm, with `1` notation per line:
 
 * in the best case
 * in the average case
@@ -349,3 +348,57 @@ alex@/tmp/sort$ ./select
 7, 13, 19, 48, 52, 71, 73, 86, 96, 99
 alex@/tmp/sort$
 ```
+
+[3. Quick sort](./3-quick_sort.c)
+
+Write a function that sorts an array of integers in ascending order using the [Quick sort](https://en.wikipedia.org/wiki/Quicksort) algorithm
+
+* Prototype: `void quick_sort(int *array, size_t size);`
+* You must implement the `Lomuto` partition scheme.
+* The pivot should always be the last element of the partition being sorted.
+* You’re expected to print the `array` after each time you swap two elements (See example below)
+
+Write in the file `3-O`, the big O notations of the time complexity of the `Quick sort` algorithm, with `1` notation per line:
+
+* in the best case
+* in the average case
+* in the worst case
+
+```
+alex@/tmp/sort$ cat 3-main.c
+#include <stdio.h>
+#include <stdlib.h>
+#include "sort.h"
+
+/**
+ * main - Entry point
+ *
+ * Return: Always 0
+ */
+int main(void)
+{
+    int array[] = {19, 48, 99, 71, 13, 52, 96, 73, 86, 7};
+    size_t n = sizeof(array) / sizeof(array[0]);
+
+    print_array(array, n);
+    printf("\n");
+    quick_sort(array, n);
+    printf("\n");
+    print_array(array, n);
+    return (0);
+}
+alex@/tmp/sort$ gcc -Wall -Wextra -Werror -pedantic  -std=gnu89 3-main.c 3-quick_sort.c print_array.c -o quick
+alex@/tmp/sort$ ./quick
+19, 48, 99, 71, 13, 52, 96, 73, 86, 7
+
+7, 48, 99, 71, 13, 52, 96, 73, 86, 19
+7, 13, 99, 71, 48, 52, 96, 73, 86, 19
+7, 13, 19, 71, 48, 52, 96, 73, 86, 99
+7, 13, 19, 71, 48, 52, 73, 96, 86, 99
+7, 13, 19, 71, 48, 52, 73, 86, 96, 99
+7, 13, 19, 48, 71, 52, 73, 86, 96, 99
+7, 13, 19, 48, 52, 71, 73, 86, 96, 99
+
+7, 13, 19, 48, 52, 71, 73, 86, 96, 99
+alex@/tmp/sort$
+```