Problem:
Merge Sort

Write a program of a Merge Sort algorithm implemented by the following pseudocode. You should also report the number of comparisons in the Merge function.

Merge(A, left, mid, right)
n1 = mid - left;
n2 = right - mid;
create array L[0...n1], R[0...n2]
for i = 0 to n1-1
do L[i] = A[left + i]
for i = 0 to n2-1
do R[i] = A[mid + i]
L[n1] = SENTINEL
R[n2] = SENTINEL
i = 0;
j = 0;
for k = left to right-1
if L[i] <= R[j]
then A[k] = L[i]
i = i + 1
else A[k] = R[j]
j = j + 1

Merge-Sort(A, left, right){
if left+1 < right
then mid = (left + right)/2;
call Merge-Sort(A, left, mid)
call Merge-Sort(A, mid, right)
call Merge(A, left, mid, right)

Input

In the first line n is given. In the second line, n integers are given.

Output

In the first line, print the sequence S. Two consequtive elements should be separated by a space character.

In the second line, print the number of comparisons.

Constraints

n ≤ 500000

0 ≤ an element in S ≤ 109

Sample Input 1

10
8 5 9 2 6 3 7 1 10 4

Sample Output 1

1 2 3 4 5 6 7 8 9 10
34

Notes

Solution in C (judge verdict: Accepted)

#include <stdio.h>
#include <limits.h>
#define MAX_LENGTH 500000
int counter=0;
void Merge(int arr[], int left, int middle, int right)
{
    int n1 = middle - left;
    int n2= right - middle;
    int L[n1+1], R[n2+1];
    for(int i=0;i<n1;i++){L[i]=arr[left+i];}
    for(int i=0;i<n2;i++){R[i]=arr[middle+i];}
    L[n1] = INT_MAX;
    R[n2] = INT_MAX;
    int i=0;
    int j=0;
    for(int k=left;k<right;k++)
    {
        if(L[i]<=R[j])
        {
            arr[k] = L[i];
            i += 1;
        }
        else{
            arr[k] = R[j];
            j += 1;
        }
        counter++;
    }
}
void MergeSort(int arr[], int left, int right)
{
    if(left+1 < right)
    {
        int middle = (left + right)/2;
        MergeSort(arr, left, middle);
        MergeSort(arr, middle, right);
        Merge(arr, left, middle, right);
    }
}
int main() {
    int num=0;
    int A[MAX_LENGTH]={0};
    scanf("%d", &num);
    for(int i=0;i<num;i++){scanf("%d", &A[i]);}
    MergeSort(A, 0, num);
    for(int i=0;i<num;i++)
    {
        if(i!=num-1){printf("%d ", A[i]);}
        else{printf("%d\n", A[i]);}
    }
    printf("%d\n", counter);
    return 0;
}