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 (Clang 3.8.0) (judge verdict: Time Limit Exceeded)

#include<stdio.h>
const int MAX=100000;
struct xian{
	int num;
	int slm;
}xr[MAX];
int main()
{int n;
scanf("%d",&n);
int i,j;
for(i=0;i<n;i++)
{scanf("%d",&xr[i].num);
xr[i].slm=0;
}
int count=n;
for(i=0;i<n;i++)
{if(xr[i].slm==0)
for(j=i+1;j<n;j++)
{if(xr[j].num==xr[i].num&&xr[j].slm==0){count=count-2;xr[j].slm=1;break;}
}
}
printf("%d\n",count);
return 0;
 }