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 <iostream>
#include <cstdio>
#include <cstring>
#include <cmath>
#include <string>
#include <algorithm>
#define inf 0x3f3f3f3f
#define LL long long

using namespace std;

int main()
{
    LL n;
    LL c[100005];
    while(scanf("%lld",&n)!=EOF)
    {
        memset(c,0,sizeof c);
        for(int i=0;i<n;i++)
        {
            scanf("%lld",&c[i]);
        }
        sort(c,c+n);
        LL a=c[0];
        LL sum=0,ans=0;
        for(LL i=0;i<n;i++)
        {
            if(a==c[i])
            {
                sum++;
            }
            else
            {
                if(sum%2==1)
                {
                    ans++;
                }
                sum=1;
                a=c[i];
            }
        }
        printf("%lld\n",ans);
    }
    return 0;
}