CPC '21 Contest 1 P2 - AQT and Multiset
View as PDFAQT has two multisets of integers  and 
, both of size 
 for some non-negative integer 
. Help AQT determine the smallest non-negative integer 
 such that after XOR-ing each element in 
 by 
, the multisets 
 and 
 are equal.
Constraints
In all subtasks,
Subtask 1 [5%]
Subtask 2 [15%]
Subtask 3 [80%]
No additional constraints.
Input Specification
The first line contains one integer .
The second line contains  space separated integers, 
.
The third line contains  space separated integers, 
.
Output Specification
Output the smallest possible value of  as described above on a single line. If no such value exists, output 
-1 on a single line.
Sample Input 1
3
84 80 88 84 93 84 86
5 1 12 7 9 5 5
Sample Output 1
81
Explanation of Sample Output 1
The smallest possible solution is . If we XOR each element in 
 by 
, we have 
, which is equivalent to 
.
Sample Input 2
1
3 1 9
1 12 123
Sample Output 2
-1
Comments