Sorting Programs added in C and C++

Sorting/mergesort.c

@@ -0,0 +1,86 @@
+#include<stdlib.h> 
+#include<stdio.h> 
+
+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 printArray(int A[], int size) 
+{ 
+	int i; 
+	for (i=0; i < size; i++) 
+		printf("%d ", A[i]); 
+	printf("\n"); 
+} 
+
+int main() 
+{ 
+	int n;
+	scanf("%d",&n);
+	int arr[n];
+	for(int i=0;i<n;i++)
+		scanf("%d",&arr[i]);
+
+	printf("Given array is \n"); 
+	printArray(arr, arr_size); 
+
+	mergeSort(arr, 0, arr_size - 1); 
+
+	printf("\nSorted array is \n"); 
+	printArray(arr, arr_size); 
+	return 0; 
+} 

Sorting/mergesort.cpp

@@ -0,0 +1,87 @@
+#include <iostream>
+using namespace std;
+
+
+void merge(int a[], int n1, int b[], int n2, int arr[])
+{
+  int i=0,j=0,k=0;
+  cout<<endl;
+  while(i<n1)
+  {
+  	cout<<a[i]<<" ";
+  	i++;
+  }
+  cout<<endl;
+  while(j<n2)
+  {
+  	cout<<b[j]<<" ";
+  	j++;
+  }
+i=0;j=0;
+  while(i<n1&&j<n2)
+  {
+    if(a[i]<b[j])
+    {
+      arr[k]=a[i];
+      i++;
+    }
+    else
+    {
+      arr[k]=b[j];
+      j++;
+    }
+    k++;
+  }
+  while(i<n1)
+  {
+    arr[k]=a[i];
+    k++;
+    i++;
+  }
+  while(j<n2)
+  {
+    arr[k]=b[j];
+    k++;
+    j++;
+  }
+}
+void mergeSort(int input[], int n){
+
+  if(n==0||n==1)
+    return;
+  else
+  {
+    int mid=(n-1)/2;
+    int n1=mid+1;
+    int n2=n-mid-1;
+    int a[n1],b[n2];
+    for(int i=0;i<n1;i++)
+      {
+      	a[i]=input[i];
+      }
+    int k=0;
+    for(int j=mid+1;j<n;j++)
+    {
+      b[k]=input[j];
+      k++;
+    }
+    mergeSort(a,n1);
+    mergeSort(b,n2);
+    merge(a,n1,b,n2,input);
+  }
+
+}
+int main()
+{
+  int n;
+  cin>>n;
+  int arr[n];
+  for(int i=0;i<n;i++)
+    cin>>arr[i];
+
+  mergeSort(arr,n);
+  for(int i=0;i<n;i++)
+    cout<<arr[i]<<" ";
+}
+
+

Sorting/quicksort.c

@@ -0,0 +1,55 @@
+#include<stdio.h> 
+
+void swap(int* a, int* b) 
+{ 
+	int t = *a; 
+	*a = *b; 
+	*b = t; 
+} 
+int partition (int arr[], int low, int high) 
+{ 
+	int pivot = arr[high]; 
+	int i = (low - 1);  
+
+	for (int j = low; j <= high- 1; j++) 
+	{ 
+		if (arr[j] <= pivot) 
+		{ 
+			i++; 
+			swap(&arr[i], &arr[j]); 
+		} 
+	} 
+	swap(&arr[i + 1], &arr[high]); 
+	return (i + 1); 
+} 
+
+void quickSort(int arr[], int low, int high) 
+{ 
+	if (low < high) 
+	{ 
+		int pi = partition(arr, low, high); 
+		quickSort(arr, low, pi - 1); 
+		quickSort(arr, pi + 1, high); 
+	} 
+} 
+
+void printArray(int arr[], int size) 
+{ 
+	int i; 
+	for (i=0; i < size; i++) 
+		printf("%d ", arr[i]); 
+	printf("n"); 
+} 
+
+int main() 
+{ 
+	int n;
+	scanf("%d",&n);
+	int arr[n];
+	for(int i=0;i<n;i++)
+		scanf("%d",&arr[i]);
+	quickSort(arr, 0, n-1); 
+	printf("Sorted array: n"); 
+	printArray(arr, n); 
+	return 0; 
+} 

Sorting/quicksort.cpp

@@ -0,0 +1,60 @@
+#include <iostream>
+using namespace std;
+
+
+void swap(int& a, int& b)
+{
+  int t=a;
+  a=b;
+  b=t;
+}
+
+int partition(int input[], int n)
+{
+  int p=input[0];
+  int count=0;
+  for(int i=0;i<n;i++)
+    if(input[i]<p)
+      count++;
+  swap(input[0],input[count]);
+  int i=0,j=n-1;
+  while(i<count&&j>count)
+  {
+    if(input[i]<p)
+      i++;
+    else if(input[j]>=p)
+      j--;
+    else
+    {
+      swap(input[i],input[j]);
+      i++;
+      j--;
+    }
+  }
+  return count;
+}
+
+void quickSort(int input[], int n) {
+  if(n==0||n==1)
+    return;
+  else
+  {
+    int p=partition(input,n);
+    quickSort(input,p);
+    quickSort(input+p+1,n-p-1);
+  }
+
+}
+
+int main()
+{
+	int n;
+	cin>>n;
+	int arr[n];
+	for(int i=0;i<n;i++)
+		cin>>arr[i];
+
+	quickSort(arr,n);
+	for(int i=0;i<n;i++)
+		cout<<arr[i]<<" ";
+}