Problem:
Set Symmetric Difference

Find the symmetric difference of two sets $A = \{a_0, a_1, ..., a_{n-1}\}$ and $B = \{b_0, b_1, ..., b_{m-1}\}$.

Input

The input is given in the following format.

$n$
$a_0 \; a_1 \; ... \; a_{n-1}$
$m$
$b_0 \; b_1 \; ... \; b_{m-1}$

Elements in $A$ and $B$ are given in ascending order. There are no duplicate elements in each set.

Output

Print elements in the symmetric difference in ascending order. Print an element in a line.

Constraints

$1 \leq n, m \leq 200,000$

$0 \leq a_0 < a_1 < ... < a_{n-1} \leq 10^9$

$0 \leq b_0 < b_1 < ... < b_{m-1} \leq 10^9$

Sample Input 1

7
1 2 3 4 5 6 7
4
2 4 6 8

Sample Output 1

1
3
5
7
8

Solution in C (judge verdict: Accepted)

/*
 * FileName:     set_difference
 * CreatedDate:  2020-06-09 16:18:09 +0900
 * LastModified: 2020-06-09 16:25:27 +0900
 */

#include <stdio.h>
#include <stdlib.h>
#define ultra 2e9
int main(void){
    int n;scanf("%d",&n);
    int *a = malloc((n+1)*sizeof(int));
    for(int i=0;i<n;i++)scanf("%d",a+i);
    a[n]=ultra;
    int m;scanf("%d",&m);
    int *b = malloc((m+1)*sizeof(int));
    for(int i=0;i<m;i++)scanf("%d",b+i);
    b[m]=ultra;
    int ia=0,ib=0;
    while(ia<n||ib<m){
        if(a[ia]<b[ib]){
            printf("%d\n",a[ia]);
            ia++;
        }
        else if(a[ia]>b[ib]){
            printf("%d\n",b[ib]);
            ib++;
        }
        else{
            ia++;
            ib++;
        }
    }
    free(a);
    free(b);
    return 0;
}