refined and optimized version of your Timsort implementation

Tim_sort.cpp

@@ -1,107 +1,106 @@
-#include <iostream>  
-using namespace std;  
-const int RUN = 32;  
-int min(int a, int b)    
-{    
-    if(a<b)    
-    return a;     
-    else     
-    return b;     
-}    
-/* This function sorts array from starting index to ending index which is of size atmost RUN */  
-void insertionSort(int a[], int beg, int end) /* function to sort an array with insertion sort */  
-{  
-    int i, j, temp;  
-    for (i = beg + 1; i <= end; i++) {  
-        temp = a[i];  
-        j = i - 1;  
-
-        while(j>=0 && temp <= a[j])    
-        {    
-            a[j+1] = a[j];     
-            jj = j-1;    
-        }    
-        a[j+1] = temp;    
-    }  
-}  
-/* Function to merge the sorted runs */  
-void merge(int a[], int beg, int mid, int end)    
-{    
-    int i, j, k;  
-    int n1 = mid - beg + 1;    
-    int n2 = end - mid;       
-    int LeftArray[n1], RightArray[n2]; //temporary arrays      
-    /* copy data to temp arrays */  
-    for (int i = 0; i < n1; i++)    
-    LeftArray[i] = a[beg + i];    
-    for (int j = 0; j < n2; j++)    
-    RightArray[j] = a[mid + 1 + j];        
-    i = 0;   
-    j = 0;  
-    k = beg;       
-    while (i < n1 && j < n2)    
-    {    
-        if(LeftArray[i] <= RightArray[j])    
-        {    
-            a[k] = LeftArray[i];    
-            i++;    
-        }    
-        else    
-        {    
-            a[k] = RightArray[j];    
-            j++;    
-        }    
-        k++;    
-    }    
-    while (i<n1)    
-    {    
-        a[k] = LeftArray[i];    
-        i++;    
-        k++;    
-    }        
-    while (j<n2)    
-    {    
-        a[k] = RightArray[j];    
-        j++;    
-        k++;    
-    }    
-}  
-/* function to implement tim sort */  
-void timSort(int a[], int n)  
-{     
-    /* Sort individual subarrays of size RUN */  
-    for (int i = 0; i < n; i+=RUN)  
-        insertionSort(a, i, min((i+RUN-1), (n-1)));  
-
-    // Start merging from size RUN (or 32).  
-    for (int size = RUN; size < n; size = 2*size)  
-    {  
-        for (int beg = 0; beg < n; beg += 2*size)  
-        {  
-            /* find ending point of left sub array. The starting point of right sub array is mid + 1 */  
-            int mid = beg + size - 1;  
-            int end = min((beg + 2*size - 1),(n-1));  
-
-            /* Merge subarray a[beg...mid] and a[mid+1...end] */  
-            if(mid < end)  
-                merge(a, beg, mid, end);  
-        }  
-    }  
-}  
-/* function to print the array elements */  
-void printArr(int a[], int n)  
-{  
-    for (int i = 0; i < n; i++)  
-        cout<<a[i]<<" ";  
-}  
-int main()  
-{  
-    int a[] = { 39, 11, 30, 26, 24, 7, 0, 31, 16 };  
-    int n = sizeof(a) / sizeof(a[0]);  
-    cout<<"Before sorting array elements are - \n";  
-    printArr(a, n);  
-    timSort(a, n);  
-    cout<<"\nAfter sorting array elements are - \n";    
-    printArr(a, n);  
-    return 0;  
-}  
+#include <iostream>
+using namespace std;
+
+const int RUN = 32; // Size of the run
+
+// Utility function to find the minimum of two integers
+int min(int a, int b) {
+    return (a < b) ? a : b;
+}
+
+// Insertion sort for sorting a small section of the array
+void insertionSort(int a[], int beg, int end) {
+    for (int i = beg + 1; i <= end; i++) {
+        int temp = a[i];
+        int j = i - 1;
+
+        while (j >= beg && temp < a[j]) {
+            a[j + 1] = a[j];
+            j--;
+        }
+        a[j + 1] = temp;
+    }
+}
+
+// Merge two sorted subarrays
+void merge(int a[], int beg, int mid, int end) {
+    int n1 = mid - beg + 1;
+    int n2 = end - mid;
+
+    // Temporary arrays to hold the split parts
+    int* LeftArray = new int[n1];
+    int* RightArray = new int[n2];
+
+    // Copy data to temporary arrays
+    for (int i = 0; i < n1; i++)
+        LeftArray[i] = a[beg + i];
+    for (int j = 0; j < n2; j++)
+        RightArray[j] = a[mid + 1 + j];
+
+    int i = 0, j = 0, k = beg;
+
+    // Merge the temporary arrays back into the original array
+    while (i < n1 && j < n2) {
+        if (LeftArray[i] <= RightArray[j]) {
+            a[k++] = LeftArray[i++];
+        } else {
+            a[k++] = RightArray[j++];
+        }
+    }
+
+    // Copy remaining elements, if any
+    while (i < n1) {
+        a[k++] = LeftArray[i++];
+    }
+    while (j < n2) {
+        a[k++] = RightArray[j++];
+    }
+
+    // Clean up
+    delete[] LeftArray;
+    delete[] RightArray;
+}
+
+// Timsort implementation
+void timSort(int a[], int n) {
+    // Sort individual subarrays of size RUN
+    for (int i = 0; i < n; i += RUN) {
+        insertionSort(a, i, min(i + RUN - 1, n - 1));
+    }
+
+    // Start merging from size RUN (or 32)
+    for (int size = RUN; size < n; size *= 2) {
+        for (int beg = 0; beg < n; beg += 2 * size) {
+            int mid = beg + size - 1;
+            int end = min(beg + 2 * size - 1, n - 1);
+
+            // Merge subarrays a[beg...mid] and a[mid+1...end]
+            if (mid < end) {
+                merge(a, beg, mid, end);
+            }
+        }
+    }
+}
+
+// Function to print the array elements
+void printArr(int a[], int n) {
+    for (int i = 0; i < n; i++)
+        cout << a[i] << " ";
+    cout << endl;
+}
+
+// Main function
+int main() {
+    int a[] = { 39, 11, 30, 26, 24, 7, 0, 31, 16 };
+    int n = sizeof(a) / sizeof(a[0]);
+
+    cout << "Before sorting array elements are:\n";
+    printArr(a, n);
+
+    timSort(a, n);
+
+    cout << "After sorting array elements are:\n";
+    printArr(a, n);
+
+    return 0;
+}