Merge pull request #85 from IRFANSARI/main

Added Merge Sort algorithm in CPP under CPP/Sorting-Algorithm folder

CPP/SORTING_ALGORITHMS/MergeSort.cpp

@@ -0,0 +1,75 @@
+#include <iostream>
+using namespace std;
+
+void merge(int arr[], int left, int mid, int right) {
+    int n1 = mid - left + 1;
+    int n2 = right - mid;
+
+    // Temporary arrays
+    int leftArray[n1], rightArray[n2];
+
+    // Copy data to temporary arrays
+    for (int i = 0; i < n1; i++)
+        leftArray[i] = arr[left + i];
+    for (int j = 0; j < n2; j++)
+        rightArray[j] = arr[mid + 1 + j];
+
+    // Merge the temporary arrays back into arr[left..right]
+    int i = 0, j = 0, k = left;
+    while (i < n1 && j < n2) {
+        if (leftArray[i] <= rightArray[j]) {
+            arr[k] = leftArray[i];
+            i++;
+        } else {
+            arr[k] = rightArray[j];
+            j++;
+        }
+        k++;
+    }
+
+    // Copy the remaining elements of leftArray[], if any
+    while (i < n1) {
+        arr[k] = leftArray[i];
+        i++;
+        k++;
+    }
+
+    // Copy the remaining elements of rightArray[], if any
+    while (j < n2) {
+        arr[k] = rightArray[j];
+        j++;
+        k++;
+    }
+}
+
+void mergeSort(int arr[], int left, int right) {
+    if (left < right) {
+        int mid = left + (right - left) / 2;
+
+        // Sort first and second halves
+        mergeSort(arr, left, mid);
+        mergeSort(arr, mid + 1, right);
+
+        // Merge the sorted halves
+        merge(arr, left, mid, right);
+    }
+}
+
+int main() {
+    int arr[] = {12, 11, 13, 5, 6, 7};
+    int arrSize = sizeof(arr) / sizeof(arr[0]);
+
+    cout << "Original array:\n";
+    for (int i = 0; i < arrSize; i++)
+        cout << arr[i] << " ";
+    cout << endl;
+
+    mergeSort(arr, 0, arrSize - 1);
+
+    cout << "Sorted array:\n";
+    for (int i = 0; i < arrSize; i++)
+        cout << arr[i] << " ";
+    cout << endl;
+
+    return 0;
+}