Problem:
Score : 400 points

Problem Statement

You have a sequence A composed of N positive integers: A_{1}, A_{2}, \cdots, A_{N}.

You will now successively do the following Q operations:

In the i-th operation, you replace every element whose value is B_{i} with C_{i}.

For each i (1 \leq i \leq Q), find S_{i}: the sum of all elements in A just after the i-th operation.

Constraints

All values in input are integers.

1 \leq N, Q, A_{i}, B_{i}, C_{i} \leq 10^{5}

B_{i} \neq C_{i}

Input

Input is given from Standard Input in the following format:

N
A_{1} A_{2} \cdots A_{N}
Q
B_{1} C_{1}
B_{2} C_{2}
\vdots
B_{Q} C_{Q}

Output

Print Q integers S_{i} to Standard Output in the following format:

S_{1}
S_{2}
\vdots
S_{Q}

Note that S_{i} may not fit into a 32-bit integer.

Sample Input 1

4
1 2 3 4
3
1 2
3 4
2 4

Sample Output 1

11
12
16

Initially, the sequence A is 1,2,3,4.

After each operation, it becomes the following:

2, 2, 3, 4

2, 2, 4, 4

4, 4, 4, 4

Sample Input 2

4
1 1 1 1
3
1 2
2 1
3 5

Sample Output 2

8
4
4

Note that the sequence A may not contain an element whose value is B_{i}.

Sample Input 3

2
1 2
3
1 100
2 100
100 1000

Sample Output 3

102
200
2000

Solution in Rust (1.42.0) (judge verdict: Accepted)

use std::collections::HashMap;

fn main() {
    let n: i64 = read();
    let nums: Vec<i64> = read_vec();
    let q: i64 = read();
    let operates: Vec<Vec<i64>> = read_vec2(q);

    let mut num_dict = create_dict(&nums);
    let mut num_sum: i64 = num_dict.iter().map(|(key, value)| key * value).sum();

    for operate in operates.iter() {
        let b = operate[0];
        let c = operate[1];

        if let Some(b_count) = num_dict.remove(&b) {
            let c_count = match num_dict.get(&c) {
                Some(i) => i + b_count,
                None => b_count,
            };
            num_dict.insert(c, c_count);

            num_sum = num_sum + (b * -b_count) + (c * b_count);
        }
        
        println!("{}", num_sum);
    }
}

fn create_dict(nums: &Vec<i64>) -> HashMap<i64, i64> {
    let mut d: HashMap<i64, i64> = HashMap::new();
    for num in nums.iter() {
        let count: i64 = match d.get(num) {
            Some(i) => *i + 1,
            None => 1,
        };
        d.insert(*num, count);
    }
    return d;
}

fn read<T: std::str::FromStr>() -> T {
    let mut s = String::new();
    std::io::stdin().read_line(&mut s).ok();
    s.trim().parse().ok().unwrap()
}

fn read_vec<T: std::str::FromStr>() -> Vec<T> {
    read::<String>()
        .split_whitespace()
        .map(|e| e.parse().ok().unwrap())
        .collect()
}

fn read_vec2<T: std::str::FromStr>(n: i64) -> Vec<Vec<T>> {
    (0..n).map(|_| read_vec()).collect()
}