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::io::*;
use std::str::FromStr;

fn main() {
	let n: usize = read();
	let mut v: Vec<usize> = vec![0; 100001];
	let mut temp: usize;
	let mut sum: usize = 0;
	for _ in 0..n {
		temp = read();
		sum += temp;
		v[temp] += 1;
	}
	let q: usize = read();
	let mut b: usize;
	let mut c: usize;
	let mut w: Vec<usize> = Vec::new();
	for _ in 0..q {
		b = read();
		c = read();
		sum -= b * v[b];
		sum += c * v[b];
		v[c] += v[b];
		v[b] = 0;
		w.push(sum);
	}
	for i in &w {
		println!("{}", i);
	}
}

fn read<T: FromStr>() -> T {
	let stdin = stdin();
	let stdin = stdin.lock();
	let token: String = stdin
		.bytes()
		.map(|c| c.expect("failed to read char") as char)
		.skip_while(|c| c.is_whitespace())
		.take_while(|c| !c.is_whitespace())
		.collect();
	token.parse().ok().expect("failed to parse token")
}