Problem:
Score : 300 points

Problem Statement

You are playing the following game with Joisino.

Initially, you have a blank sheet of paper.

Joisino announces a number. If that number is written on the sheet, erase the number from the sheet; if not, write the number on the sheet. This process is repeated N times.

Then, you are asked a question: How many numbers are written on the sheet now?

The numbers announced by Joisino are given as A_1, ... ,A_N in the order she announces them. How many numbers will be written on the sheet at the end of the game?

Constraints

1≤N≤100000

1≤A_i≤1000000000(=10^9)

All input values are integers.

Input

Input is given from Standard Input in the following format:

N
A_1
:
A_N

Output

Print how many numbers will be written on the sheet at the end of the game.

Sample Input 1

3
6
2
6

Sample Output 1

1

The game proceeds as follows:

6 is not written on the sheet, so write 6.

2 is not written on the sheet, so write 2.

6 is written on the sheet, so erase 6.

Thus, the sheet contains only 2 in the end. The answer is 1.

Sample Input 2

4
2
5
5
2

Sample Output 2

0

It is possible that no number is written on the sheet in the end.

Sample Input 3

6
12
22
16
22
18
12

Sample Output 3

2

Solution in C++14 (GCC 5.4.1) (judge verdict: Wrong Answer)

#include <bits/stdc++.h>
using namespace std;

int main() {
	int n,sumsum=0;
	cin>>n;
	vector<long>vec(n);
	for(int i=0;i<n;i++){
		long a;
		cin>>a;
		vec.at(i)=a;
	}
	sort(vec.begin(),vec.end());
	int sum=1;
	if(n==1){
	      cout<<1<<endl;	
	}
	else{
	for(int i=0;i<n-1;i++){
		
		if(vec.at(i)==vec.at(i+1)){
			sum++;
			if(i==n-2){
				if(sum%2==1){
					sumsum++;
				}
			}
		}
		else{
			if(sum%2==1){
				sumsum++;
				
			}
			sum=1;
		}
	}
	cout<<sumsum<<endl;
	return 0;
	}
}