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 Java (OpenJDK 11.0.6) (judge verdict: Time Limit Exceeded)

import java.util.Arrays;
import java.util.HashMap;
import java.util.Map;
import java.util.Scanner;

public class Main {

  public static void main(String[] args) {
    final Scanner scanner = new Scanner(System.in);

    scanner.nextLine();
    final int[] a = Arrays.stream(scanner.nextLine().split(" "))
        .mapToInt(Integer::parseInt)
        .toArray();
    final int q = scanner.nextInt();
    scanner.nextLine();
    final int[][] bc = new int[q][2];
    for (int i = 0; i < q; i++) {
      bc[i][0] = scanner.nextInt();
      bc[i][1] = scanner.nextInt();
      scanner.nextLine();
    }

    long sum = 0;
    Map<Integer, Long> counts = new HashMap<>();
    for (int i = 0; i < a.length; i++) {
      counts.put(
          a[i],
          counts.containsKey(a[i]) ? counts.get(a[i]) + 1 : 1
      );
      sum += a[i];
    }

    for (int i = 0; i < q; i++) {
      final long replaceCount = counts.containsKey(bc[i][0]) ?
                                counts.get(bc[i][0]) :
                                0L;

      if (replaceCount > 0) {
        counts.put(
            bc[i][1],
            counts.containsKey(bc[i][1]) ? counts.get(bc[i][1]) + replaceCount : replaceCount
        );
        counts.put(
            bc[i][0],
            0L
        );
      }

      sum += replaceCount * (bc[i][1] - bc[i][0]);

      System.out.println(sum);
    }
  }
}