chore(C): add quick sort (#652)

algorithms/C/README.md

@@ -45,6 +45,7 @@
 - [Insertion Sort](sorting/insertion-sort.c)
 - [Heap Sort](sorting/heap-sort.c)
 - [Selection Sort](sorting/selection-sort.c)
+- [Quick Sort](sorting/quick-sort.c)
 
 ## Strings
 

algorithms/C/sorting/quick-sort.c

@@ -0,0 +1,61 @@
+// Quick Sort Algorithm in C
+
+#include <stdio.h>
+
+// Function to swap two elements
+void swap(int *a, int *b)
+{
+    int temp = *a;
+    *a = *b;
+    *b = temp;
+}
+
+/* This function takes first element as pivot, places the pivot element at its correct position in sorted array, 
+and places all smaller (smaller than pivot) to left of pivot and all greater elements to right of pivot.*/
+int Partition(int a[], int low, int high)
+{
+    int pivot = a[low];
+    int start = low;
+    int end = high;
+
+    while (start < end)
+    {
+        while (a[start] <= pivot)
+            start++;
+        while (a[end] > pivot)
+            end--;
+        if (start < end)
+        {
+            swap(&a[start], &a[end]);
+        }
+    }
+    swap(&a[low], &a[end]);
+    return end;
+}
+
+// Recursive function to sort an array using quick sort
+void Quicksort(int a[], int low, int high)
+{
+    if (low < high)
+    {
+        int pivot = Partition(a, low, high);
+        Quicksort(a, low, pivot - 1);
+        Quicksort(a, pivot + 1, high);
+    }
+}
+
+int main()
+{
+    int a[] = {5, 2, 4, 6, 1, 3};
+    int n = sizeof(a) / sizeof(a[0]);
+    Quicksort(a, 0, n - 1);
+    for (int i = 0; i < n; i++){
+        printf("%d ", a[i]);
+    }
+    return 0;
+}
+
+/*
+Output:
+1 2 3 4 5 6
+*/