Problem:
Score : 1000 points

Problem Statement

There is a sequence of length N: a = (a_1, a_2, ..., a_N).
Here, each a_i is a non-negative integer.

Snuke can repeatedly perform the following operation:

Let the XOR of all the elements in a be x. Select an integer i (1 ≤ i ≤ N) and replace a_i with x.

Snuke's objective is to match a with another sequence b = (b_1, b_2, ..., b_N).
Here, each b_i is a non-negative integer.

Determine whether the objective is achievable, and find the minimum necessary number of operations if the answer is positive.

Constraints

2 ≤ N ≤ 10^5

a_i and b_i are integers.

0 ≤ a_i, b_i < 2^{30}

Input

Input is given from Standard Input in the following format:

N
a_1 a_2 ... a_N
b_1 b_2 ... b_N

Output

If the objective is achievable, print the minimum necessary number of operations.
Otherwise, print -1 instead.

Sample Input 1

3
0 1 2
3 1 0

Sample Output 1

2

At first, the XOR of all the elements of a is 3.
If we replace a_1 with 3, a becomes (3, 1, 2).

Now, the XOR of all the elements of a is 0.
If we replace a_3 with 0, a becomes (3, 1, 0), which matches b.

Sample Input 2

3
0 1 2
0 1 2

Sample Output 2

0

Sample Input 3

2
1 1
0 0

Sample Output 3

-1

Sample Input 4

4
0 1 2 3
1 0 3 2

Sample Output 4

5

Solution in Rust (1.15.1) (judge verdict: Accepted)

macro_rules! input {
    (source = $s:expr, $($r:tt)*) => {
        let mut iter = $s.split_whitespace();
        let mut next = || { iter.next().unwrap() };
        input_inner!{next, $($r)*}
    };
    ($($r:tt)*) => {
        let stdin = std::io::stdin();
        let mut bytes = std::io::Read::bytes(std::io::BufReader::new(stdin.lock()));
        let mut next = move || -> String {
            bytes
                .by_ref()
                .map(|r| r.unwrap() as char)
                .skip_while(|c| c.is_whitespace())
                .take_while(|c| !c.is_whitespace())
                .collect()
        };
        input_inner!{next, $($r)*}
    };
}

macro_rules! input_inner {
    ($next:expr) => {};
    ($next:expr, ) => {};

    ($next:expr, $var:ident : $t:tt $($r:tt)*) => {
        let $var = read_value!($next, $t);
        input_inner!{$next $($r)*}
    };

    ($next:expr, mut $var:ident : $t:tt $($r:tt)*) => {
        let mut $var = read_value!($next, $t);
        input_inner!{$next $($r)*}
    };
}

macro_rules! read_value {
    ($next:expr, ( $($t:tt),* )) => {
        ( $(read_value!($next, $t)),* )
    };

    ($next:expr, [ $t:tt ; $len:expr ]) => {
        (0..$len).map(|_| read_value!($next, $t)).collect::<Vec<_>>()
    };

    ($next:expr, [ $t:tt ]) => {
        {
            let len = read_value!($next, usize);
            (0..len).map(|_| read_value!($next, $t)).collect::<Vec<_>>()
        }
    };

    ($next:expr, chars) => {
        read_value!($next, String).chars().collect::<Vec<char>>()
    };

    ($next:expr, usize1) => {
        read_value!($next, usize) - 1
    };

    ($next:expr, $t:ty) => {
        $next().parse::<$t>().expect("Parse error")
    };
}

#[allow(unused_imports)]
use std::cmp::{min, max};

fn main() {
    input!{
        n: usize,
        mut a: [usize; n],
        mut b: [usize; n]
    }
    let al = a.iter().fold(0, |ac, x| ac ^ x);
    let bl = b.iter().fold(0, |ac, x| ac ^ x);
    a.push(al);
    b.push(bl);
    let mut mapa = HashMap::new();
    let mut mapb = HashMap::new();
    for i in 0..n + 1 {
        *mapa.entry(a[i]).or_insert(0) += 1;
        *mapb.entry(b[i]).or_insert(0) += 1;
    }
    if mapa != mapb {
        println!("-1");
        return;
    }
    let mut ans = 0;
    let mut uf = UnionFind::new();
    for i in 0..n {
        if a[i] == b[i] {
            continue;
        }
        ans += 1;
        uf.union(a[i], b[i]);
    }
    uf.union(a[n],b[n]);
    println!("{}", ans + uf.n_unions() - 1);
}

use std::collections::{HashSet, HashMap};

#[derive(Clone)]
struct UFNode {
    parent: usize,
    rank: usize,
    size: usize
}

struct UnionFind<T> where T: std::cmp::Eq + std::hash::Hash {
    map: HashMap<T,usize>,
    nodes: Vec<UFNode>,
    next: usize,
    n_unions: usize
}

impl<T: std::cmp::Eq + std::hash::Hash> UnionFind<T> {
    fn new() -> UnionFind<T> {
        UnionFind{map: HashMap::new(), nodes: Vec::new(), next: 0, n_unions: 0}
    }

    fn new_points(v: Vec<T>) -> UnionFind<T> {
        let mut uf = UnionFind::new();
        for x in v {
            if uf.map.contains_key(&x) {
                continue;
            }
            uf.add_point(x);
        }
        uf
    }

    fn add_point(&mut self, x: T) -> usize {
        let id = self.next;
        self.map.insert(x,id);
        self.nodes.push(UFNode{parent: id, rank: 0, size: 1});
        self.next += 1;
        self.n_unions += 1;
        id
    }

    fn get_id(&self, x: &T) -> Option<usize> {
        self.map.get(x).map(|x| *x)
    }

    fn find(&mut self, id: usize) -> usize {
        let p = self.nodes[id].parent;
        if p == id {
            return id;
        }
        let pr = self.find(p);
        self.nodes[id].parent = pr;
        pr
    }

    fn union(&mut self, x: T, y: T) {
        let idx = self.get_id(&x).unwrap_or_else(|| self.add_point(x));
        let idy = self.get_id(&y).unwrap_or_else(|| self.add_point(y));
        let xp = self.find(idx);
        let yp = self.find(idy);
        if xp == yp {
            return;
        }
        let rx = self.nodes[xp].rank;
        let ry = self.nodes[yp].rank;
        if rx < ry {
            self.nodes[xp].parent = yp;
        } else if rx > ry {
            self.nodes[yp].parent = xp;
        } else {
            self.nodes[yp].parent = xp;
            self.nodes[xp].rank += 1;
        }
        let size = self.nodes[xp].size + self.nodes[yp].size;
        self.nodes[xp].size = size;
        self.nodes[yp].size = size;
        self.n_unions -= 1;
    }

    fn is_same(&mut self, x: &T, y: &T) -> bool {
        let idx = self.get_id(x);
        let idy = self.get_id(y);
        if idx == None || idy == None {
            false
        } else {
            self.find(idx.unwrap()) == self.find(idy.unwrap())
        }
    }

    fn n_points(&self) -> usize {
        self.next
    }

    fn n_unions(&self) -> usize {
        self.n_unions
    }

    fn group_id(&mut self, x: &T) -> usize {
        let id = self.get_id(x).unwrap();
        self.find(id)
    }

    fn size(&mut self, x: &T) -> usize {
        let id = self.get_id(x).unwrap();
        let idp = self.find(id);
        self.nodes[idp].size
    }

    fn to_sets(&mut self) -> HashMap<usize,HashSet<T>> where T: Clone {
        let mut map: HashMap<usize, HashSet<T>> = HashMap::new();
        for (k, v) in self.map.clone() {
            let s = map.entry(self.find(v)).or_insert_with(HashSet::new);
            s.insert(k);
        }
        map
    }
}


impl<T: Clone + std::cmp::Eq + std::hash::Hash> Clone for UnionFind<T> {
    fn clone(&self) -> Self {
        UnionFind{map: self.map.clone(), nodes: self.nodes.clone(), next: self.next, n_unions: self.n_unions}
    }
}