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>

#define MAX 500000
#define SIZE 1000000001

int cnt = 0;
int array [MAX];
int LEFT [MAX], RIGHT [MAX];

int main() {
	int number;
	scanf("%d", &number);
	for (int i = 0; i < number; i++) {
		scanf("%d", &array[i]);
	}
	mergeSort(array, 0, number);

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

void merge(int array[], int left, int mid, int right) {
	int num1 = mid - left;
	int num2 = right - mid;
	int I, J;
	for (int i = 0; i < num1; i++) {
		LEFT[i] = array[left + i];
	}
	for (int i = 0; i < num2; i++) {
		RIGHT[i] = array[mid + i];
	}
	LEFT[num1] = SIZE; RIGHT[num2] = SIZE;
	I = 0; J = 0;
	for (int k = left; k < right; k++) {
		if (LEFT[I] <= RIGHT[J]) {
			array[k] = LEFT[I];
			I++;
			cnt++;
		}
		else {
			array[k] = RIGHT[J];
			J++;
			cnt++;
		}
	}
}

void mergeSort(int array[], int left, int right) {
	if (left + 1 == right)return;
	int mid = (left + right) / 2;
	mergeSort(array, left, mid);
	mergeSort(array, mid, right);
	merge(array, left, mid, right);
}