Merge Sort

Merge Sort.cpp

@@ -0,0 +1,99 @@
+#include<iostream>
+using namespace std;
+
+void merge(int arr[], int l, int m, int r)
+{
+    int i, j, k;
+    int n1 = m - l + 1;
+    int n2 =  r - m;
+ 
+    int L[n1], R[n2];
+ 
+   
+    for (i = 0; i < n1; i++)
+        L[i] = arr[l + i];
+    for (j = 0; j < n2; j++)
+        R[j] = arr[m + 1+ j];
+ 
+    i = 0;
+    j = 0;
+    k = l;
+    while (i < n1 && j < n2)
+    {
+        if (L[i] <= R[j])
+        {
+            arr[k] = L[i];
+            i++;
+        }
+        else
+        {
+            arr[k] = R[j];
+            j++;
+        }
+        k++;
+    }
+ 
+    while (i < n1)
+    {
+        arr[k] = L[i];
+        i++;
+        k++;
+    }
+ 
+
+    while (j < n2)
+    {
+        arr[k] = R[j];
+        j++;
+        k++;
+    }
+}
+ 
+
+void mergeSort(int arr[], int l, int r)
+{
+    if (l < r)
+    {
+       
+        int m = l+(r-l)/2;
+ 
+        
+        mergeSort(arr, l, m);
+        mergeSort(arr, m+1, r);
+ 
+        merge(arr, l, m, r);
+    }
+}
+ 
+
+void show(int A[], int size)
+{
+    int i;
+    for (i=0; i < size; i++)
+    cout<<A[i]<<"\n";
+}
+ 
+
+int main()
+{
+     int size;
+    cout<<"\nEnter the number of elements : ";
+
+    cin>>size;
+
+    int arr[size];
+    
+    cout<<"\nEnter the unsorted elements : ";
+
+    for (int i = 0; i < size; ++i)
+    {
+        cout<<"\n";
+        cin>>arr[i];
+    }
+
+    mergeSort(arr, 0, size);
+ 
+    cout<<"Sorted array\n";
+    show(arr, size);
+    return 0;
+}

Quick Sort.cpp

@@ -0,0 +1,69 @@
+/* C implementation QuickSort */
+#include<iostream>
+using namespace std;
+ 
+int partition (int arr[], int low, int high)
+{
+    int pivot = arr[high];    // pivot
+    int i = (low - 1);  // Index of smaller element
+ 
+    for (int j = low; j <high; j++)
+    {
+        // If current element is smaller than or
+        // equal to pivot
+        if (arr[j] <= pivot)
+        {
+            i++;    // increment index of smaller element
+            int temp=arr[i];
+            arr[i]=arr[j];
+            arr[j]=temp;
+        }
+    }
+    int temp=arr[i+1];
+    arr[i+1]=arr[high];
+    arr[high]=temp;
+    return (i + 1);
+}
+ 
+
+void quickSort(int arr[], int low, int high)
+{
+    if (low < high)
+    {
+       
+        int p= partition(arr, low, high);
+
+        quickSort(arr, low, p - 1);
+        quickSort(arr, p + 1, high);
+    }
+}
+ 
+
+void show(int arr[], int size)
+{
+    for (int i=0; i < size; i++)
+    cout<<arr[i]<<"\n";
+}
+ 
+// Driver program to test above functions
+int main()
+{
+    int size;
+    cout<<"\nEnter the number of elements : ";
+
+    cin>>size;
+
+    int arr[size];
+    
+    cout<<"\nEnter the unsorted elements : ";
+
+    for (int i = 0; i < size; ++i)
+    {
+        cout<<"\n";
+        cin>>arr[i];
+    }
+    quickSort(arr, 0, size);
+    cout<<"Sorted array\n";
+    show(arr, size);
+    return 0;
+}