From 057fdce7298599b7f9c454c9563ca50f9abb5b38 Mon Sep 17 00:00:00 2001
From: Ayush Majumder <126413422+dynoayush@users.noreply.github.com>
Date: Sat, 19 Oct 2024 19:24:46 +0530
Subject: [PATCH] Create the code of tim_sort.c

Tim Sort is a sorting algorithm derived from merge sort and insertion sort.
---
 sorting/tim_sort.c | 113 +++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 113 insertions(+)
 create mode 100644 sorting/tim_sort.c

diff --git a/sorting/tim_sort.c b/sorting/tim_sort.c
new file mode 100644
index 00000000..02b8d2f7
--- /dev/null
+++ b/sorting/tim_sort.c
@@ -0,0 +1,113 @@
+#include <stdio.h>   
+#include <stdlib.h> 
+#include <string.h>  
+
+#define RUN 32  // Size of the subarrays that will be sorted using insertion sort
+
+// Function to perform insertion sort on a subarray
+void insertionSort(int arr[], int l, int r) {
+    // Loop through each element from the second element in the subarray
+    for (int i = l + 1; i <= r; i++) {
+        int temp = arr[i];  // Store the current element to be positioned
+        int j = i - 1;
+        
+        // Shift elements that are greater than temp to one position ahead
+        while (j >= l && arr[j] > temp) {
+            arr[j + 1] = arr[j];  // Shift the larger element rightwards
+            j--;
+        }
+        arr[j + 1] = temp;  // Place the stored element at its correct position
+    }
+}
+
+// Function to merge two sorted subarrays into a single sorted array
+void merge(int arr[], int l1, int m, int r1) {
+    int len1 = m - l1 + 1;  // Length of the left subarray
+    int len2 = r1 - m;     // Length of the right subarray
+    
+    // Dynamically allocate memory for the temporary left and right subarrays
+    int *leftArr = (int *)malloc(len1 * sizeof(int));
+    int *rightArr = (int *)malloc(len2 * sizeof(int));
+
+    // Copy the values of the left and right subarrays from the main array
+    for (int i = 0; i < len1; i++)
+        leftArr[i] = arr[l1 + i];
+    for (int i = 0; i < len2; i++)
+        rightArr[i] = arr[m + 1 + i];
+
+    // Initialize pointers for traversing leftArr, rightArr, and the main array
+    int i = 0, j = 0, k = l1;
+    
+    // Merge the two subarrays back into the main array in sorted order
+    while (i < len1 && j < len2) {
+        if (leftArr[i] <= rightArr[j]) {
+            arr[k] = leftArr[i];  // Copy the smaller element from leftArr
+            i++;
+        } else {
+            arr[k] = rightArr[j];  // Copy the smaller element from rightArr
+            j++;
+        }
+        k++;  // Move to the next position in the main array
+    }
+
+    // Copy any remaining elements from leftArr (if any)
+    while (i < len1) {
+        arr[k] = leftArr[i];
+        i++;
+        k++;
+    }
+
+    // Copy any remaining elements from rightArr (if any)
+    while (j < len2) {
+        arr[k] = rightArr[j];
+        j++;
+        k++;
+    }
+
+    // Free the dynamically allocated memory for leftArr and rightArr
+    free(leftArr);
+    free(rightArr);
+}
+
+// Tim Sort implementation
+void timSort(int arr[], int n) {
+    // Sort individual subarrays of size RUN using insertion sort
+    for (int i = 0; i < n; i += RUN)
+        insertionSort(arr, i, (i + RUN - 1 < n - 1) ? i + RUN - 1 : n - 1);  
+        // Sort subarrays starting at i, and ending at either i + RUN - 1 or n - 1, whichever is smaller
+
+    // Merge sorted subarrays iteratively using merge sort technique
+    for (int size = RUN; size < n; size = 2 * size) {
+        // Merge arrays in pairs of size 'size'
+        for (int left = 0; left < n; left += 2 * size) {
+            int mid = left + size - 1;  // Define the midpoint for the merge
+            int right = (left + 2 * size - 1 < n - 1) ? left + 2 * size - 1 : n - 1;  // Define the right boundary
+
+            if (mid < right)  // If there are at least two subarrays to merge
+                merge(arr, left, mid, right);  // Merge them
+        }
+    }
+}
+
+// Utility function to print the elements of the array
+void printArray(int arr[], int n) {
+    for (int i = 0; i < n; i++)  // Iterate through the array
+        printf("%d ", arr[i]);  // Print each element followed by a space
+    printf("\n");  // Print a new line after the array
+}
+
+int main() {
+    // Initialize the array to be sorted
+    int arr[] = {20, 21, 7, 23, 19, 15, 12, 7, 22, 9, 4};  // Unsorted array
+    int n = sizeof(arr) / sizeof(arr[0]);  // Calculate the number of elements in the array
+
+    printf("Original array:\n");
+    printArray(arr, n);  // Print the original (unsorted) array
+
+    timSort(arr, n);  // Sort the array using Tim Sort
+
+    printf("Sorted array:\n");
+    printArray(arr, n);  // Print the sorted array
+
+    return 0;  // End the program
+}