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>
int A[5000100];
int L[2500100];
int R[2500100];
int INFTY = 999999999;
int k;
int cnt;
void merge(int left, int mid, int right){
  int i,j;
  int n1 = mid - left;
  int n2 = right - mid;
  for (i = 0;i <= n1-1;i++)
    L[i] = A[left + i];
  
  for (i = 0;i <= n2-1;i++){
    R[i] = A[mid + i];
  L[n1] = INFTY;
  R[n2] = INFTY;
  }
  i = 0;
  j = 0;

  for (k = left;k <= right-1;k++){
    cnt++;
    if (L[i] <= R[j])
      A[k] = L[i++];
    
    else 
      A[k] = R[j++];
  }
}

void mergeSort(int left, int right){
  if (left+1 < right){
    int mid = (left + right)/2;
    mergeSort(left, mid);
    mergeSort(mid, right);
    merge(left, mid, right);
  }
}

int main(){
  int i,a,b,n;

  scanf("%d",&a);
  for(i=0;i<a;i++)
    scanf("%d",&A[i]);
  
  
    mergeSort(0,a);

    for(i = 0;i < a-1;i++){
    printf("%d",A[i]);
    if(i < a-1)
      printf(" ");
    
  }
  printf("%d\n",A[a-1]);
  printf("%d\n",cnt);
return 0;
}