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<stdlib.h>
#define INFTY 2147483647;
int count=0;
void merge(int *A,int l,int m,int r){
  int *L,*R,i,j,k;
  int n1=m-l;
  int n2=r-m;

  L=(int *)malloc((n1+1)*sizeof(int));
  R=(int *)malloc((n2+1)*sizeof(int));
  for(i=0;i<n1;i++){
    L[i]=A[l+i];
  }
  for(j=0;j<n2;j++){
    R[j]=A[m+j];
  }
  
  L[n1]=R[n2]=INFTY;
  i=j=0;
  for(k=l;k<r;k++){
   
      count++;
    if(L[i]<R[j])
      {A[k]=L[i];i++;}
    else{ A[k]=R[j];j++;}
 
  }
  free(L);free(R);
}
void mergeSort(int *A,int l,int r){
  if(l+1< r){
    int m=(l+r)/2;
    mergeSort(A,l,m); 
    mergeSort(A,m,r);
    merge(A,l,m,r);
  }
  }

int main(){
    int i,j,n,A[500000];
    scanf("%d",&n);
    for(i=0;i<n;i++){
      scanf("%d",&A[i]);
    }
    
    mergeSort(A,0,n);
    for(i=0;i<n;i++){
    printf("%d",A[i]);
    if(i !=n-1)printf(" ");
    }
    printf("\n%d\n",count);
    return 0;
  }