# merge sort in c snippet in c

## sorting array in c

user7290

`````` #include <stdio.h>
void main()
{

int i, j, a, n, number[30];
printf("Enter the value of N \n");
scanf("%d", &n);

printf("Enter the numbers \n");
for (i = 0; i < n; ++i)
scanf("%d", &number[i]);

for (i = 0; i < n; ++i)
{

for (j = i + 1; j < n; ++j)
{

if (number[i] > number[j])
{

a =  number[i];
number[i] = number[j];
number[j] = a;

}

}

}

printf("The numbers arranged in ascending order are given below \n");
for (i = 0; i < n; ++i)
printf("%d\n", number[i]);
}``````

## merge sort in c

user9641

``````/* C program for Merge Sort */
#include <stdio.h>
#include <stdlib.h>

// Merges two subarrays of arr[].
// First subarray is arr[l..m]
// Second subarray is arr[m+1..r]
void merge(int arr[], int l, int m, int r)
{
int i, j, k;
int n1 = m - l + 1;
int n2 = r - m;

/* create temp arrays */
int L[n1], R[n2];

/* Copy data to temp arrays L[] and R[] */
for (i = 0; i < n1; i++)
L[i] = arr[l + i];
for (j = 0; j < n2; j++)
R[j] = arr[m + 1 + j];

/* Merge the temp arrays back into arr[l..r]*/
i = 0; // Initial index of first subarray
j = 0; // Initial index of second subarray
k = l; // Initial index of merged subarray
while (i < n1 && j < n2) {
if (L[i] <= R[j]) {
arr[k] = L[i];
i++;
}
else {
arr[k] = R[j];
j++;
}
k++;
}

/* Copy the remaining elements of L[], if there
are any */
while (i < n1) {
arr[k] = L[i];
i++;
k++;
}

/* Copy the remaining elements of R[], if there
are any */
while (j < n2) {
arr[k] = R[j];
j++;
k++;
}
}

/* l is for left index and r is right index of the
sub-array of arr to be sorted */
void mergeSort(int arr[], int l, int r)
{
if (l < r) {
// Same as (l+r)/2, but avoids overflow for
// large l and h
int m = l + (r - l) / 2;

// Sort first and second halves
mergeSort(arr, l, m);
mergeSort(arr, m + 1, r);

merge(arr, l, m, r);
}
}

/* UTILITY FUNCTIONS */
/* Function to print an array */
void printArray(int A[], int size)
{
int i;
for (i = 0; i < size; i++)
printf("%d ", A[i]);
printf("\n");
}

/* Driver program to test above functions */
int main()
{
int arr[] = { 12, 11, 13, 5, 6, 7 };
int arr_size = sizeof(arr) / sizeof(arr[0]);

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;
}
``````

## merge sort in c++

user9925

``````/* C program for Merge Sort */
#include<stdlib.h>
#include<stdio.h>

// Merges two subarrays of arr[].
// First subarray is arr[l..m]
// Second subarray is arr[m+1..r]
void merge(int arr[], int l, int m, int r)
{
int i, j, k;
int n1 = m - l + 1;
int n2 =  r - m;

/* create temp arrays */
int L[n1], R[n2];

/* Copy data to temp arrays L[] and R[] */
for (i = 0; i < n1; i++)
L[i] = arr[l + i];
for (j = 0; j < n2; j++)
R[j] = arr[m + 1+ j];

/* Merge the temp arrays back into arr[l..r]*/
i = 0; // Initial index of first subarray
j = 0; // Initial index of second subarray
k = l; // Initial index of merged subarray
while (i < n1 && j < n2)
{
if (L[i] <= R[j])
{
arr[k] = L[i];
i++;
}
else
{
arr[k] = R[j];
j++;
}
k++;
}

/* Copy the remaining elements of L[], if there
are any */
while (i < n1)
{
arr[k] = L[i];
i++;
k++;
}

/* Copy the remaining elements of R[], if there
are any */
while (j < n2)
{
arr[k] = R[j];
j++;
k++;
}
}

/* l is for left index and r is right index of the
sub-array of arr to be sorted */
void mergeSort(int arr[], int l, int r)
{
if (l < r)
{
// Same as (l+r)/2, but avoids overflow for
// large l and h
int m = l+(r-l)/2;

// Sort first and second halves
mergeSort(arr, l, m);
mergeSort(arr, m+1, r);

merge(arr, l, m, r);
}
}

/* UTILITY FUNCTIONS */
/* Function to print an array */
void printArray(int A[], int size)
{
int i;
for (i=0; i < size; i++)
printf("%d ", A[i]);
printf("\n");
}

/* Driver program to test above functions */
int main()
{
int arr[] = {12, 11, 13, 5, 6, 7};
int arr_size = sizeof(arr)/sizeof(arr[0]);

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;
}
``````

## Merge sort in c++

user5802

``````#include <iostream>
using namespace std;

void merge(int arr[], int l, int m, int r)
{
int n1 = m - l + 1;
int n2 = r - m;

int L[n1], R[n2];

for (int i = 0; i < n1; i++)
L[i] = arr[l + i];
for (int j = 0; j < n2; j++)
R[j] = arr[m + 1 + j];

int i = 0;

int j = 0;

int 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){
return;
}
int m = (l+r-1)/2;
mergeSort(arr,l,m);
mergeSort(arr,m+1,r);
merge(arr,l,m,r);
}

void printArray(int A[], int size)
{
for (int i = 0; i < size; i++)
cout << A[i] << " ";
}

int main()
{
int arr[] = { 12, 11, 13, 5, 6, 7 };
int arr_size = sizeof(arr) / sizeof(arr[0]);

cout << "Given array is \n";
printArray(arr, arr_size);

mergeSort(arr, 0, arr_size - 1);

cout << "\nSorted array is \n";
printArray(arr, arr_size);
return 0;
}``````

## merge sort

user7810

``````# Python program for implementation of MergeSort
def mergeSort(arr):
if len(arr) >1:
mid = len(arr)//2 #Finding the mid of the array
L = arr[:mid] # Dividing the array elements
R = arr[mid:] # into 2 halves

mergeSort(L) # Sorting the first half
mergeSort(R) # Sorting the second half

i = j = k = 0

# Copy data to temp arrays L[] and R[]
while i < len(L) and j < len(R):
if L[i] < R[j]:
arr[k] = L[i]
i+=1
else:
arr[k] = R[j]
j+=1
k+=1

# Checking if any element was left
while i < len(L):
arr[k] = L[i]
i+=1
k+=1

while j < len(R):
arr[k] = R[j]
j+=1
k+=1

# Code to print the list
def printList(arr):
for i in range(len(arr)):
print(arr[i],end=" ")
print()

# driver code to test the above code
if __name__ == '__main__':
arr = [12, 11, 13, 5, 6, 7]
print ("Given array is", end="\n")
printList(arr)
mergeSort(arr)
print("Sorted array is: ", end="\n")
printList(arr)

# This code is contributed by Mayank Khanna
``````

## merge sort

user7790

``````// @see https://www.youtube.com/watch?v=es2T6KY45cA&vl=en
// @see https://www.cs.usfca.edu/~galles/visualization/ComparisonSort.html

function merge(list, start, midpoint, end) {
const left = list.slice(start, midpoint);
const right = list.slice(midpoint, end);
for (let topLeft = 0, topRight = 0, i = start; i < end; i += 1) {
if (topLeft >= left.length) {
list[i] = right[topRight++];
} else if (topRight >= right.length) {
list[i] = left[topLeft++];
} else if (left[topLeft] < right[topRight]) {
list[i] = left[topLeft++];
} else {
list[i] = right[topRight++];
}
}
}

function mergesort(list, start = 0, end = undefined) {
if (end === undefined) {
end = list.length;
}
if (end - start > 1) {
const midpoint = ((end + start) / 2) >> 0;
mergesort(list, start, midpoint);
mergesort(list, midpoint, end);
merge(list, start, midpoint, end);
}
return list;
}

mergesort([4, 7, 2, 6, 4, 1, 8, 3]);``````