Problem:
Multi-Set

For a set $S$ of integers, perform a sequence of the following operations. Note that multiple elements can have equivalent values in $S$.

insert($x$): Insert $x$ to $S$ and report the number of elements in $S$ after the operation.

find($x$): Report the number of $x$ in $S$.

delete($x$): Delete all $x$ from $S$.

dump($L$, $R$): Print elements $x$ in $S$ such that $L \leq x \leq R$.

Input

The input is given in the following format.

$q$
$query_1$
$query_2$
:
$query_q$

Each query $query_i$ is given by

0 $x$

or

1 $x$

or

2 $x$

or

3 $L$ $R$

where the first digits 0, 1, 2 and 3 represent insert, find, delete and dump operations respectively.

Output

For each insert operation, print the number of elements in $S$.

For each find operation, print the number of specified elements in $S$.

For each dump operation, print the corresponding elements in ascending order. Print an element in a line.

Constraints

$1 \leq q \leq 200,000$

$0 \leq x \leq 1,000,000,000$

The total number of elements printed by dump operations does not exceed $1,000,000$

The sum of numbers printed by find operations does not exceed $2,000,000$

Sample Input 1

10
0 1
0 1
0 2
0 3
2 2
1 1
1 2
1 3
0 4
3 1 4

Sample Output 1

1
2
3
4
2
0
1
4
1
1
3
4

Solution in JAVA (judge verdict: Accepted)

import java.util.*;

class Main{
	public static void main(String[] args){
		Scanner sc = new Scanner(System.in);
		SortedMap<Integer, Integer> S = new TreeMap<Integer, Integer>();
		int q = sc.nextInt();
		int cnt = 0;
		for(int i = 0; i < q; i++){
			int com = sc.nextInt();
			if(com == 0){
				int x = sc.nextInt();
				if(S.containsKey(x)){
					int num = S.get(x);
					S.put(x, num + 1);
				}else{
					S.put(x, 1);
				}
				cnt++;
				System.out.println(cnt);
			}else if(com == 1){
				int x = sc.nextInt();
				if(S.containsKey(x)) System.out.println(S.get(x));
				else System.out.println(0);
			}else if(com == 2){
				int x = sc.nextInt();
				if(!S.containsKey(x)) continue;
				cnt -= S.get(x);
				S.remove(x);
			}else{
				int L = sc.nextInt();
				int R = sc.nextInt();
				SortedMap<Integer, Integer> SS = S.subMap(L, R + 1);
				for(Integer num : SS.keySet()){
					for(int j = 0; j < SS.get(num); j++) System.out.println(num);
				}
			}
		}
	}
}