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 1.8.0) (judge verdict: Accepted)

import java.util.*;

public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt();
        Map<Integer, Integer> countMap = new HashMap<>();
        long sum = 0;
        for (int j=0; j<n; j++) {
            int a = sc.nextInt();
            sum += a;
            Integer count = countMap.get(a);
            if (count == null) {
                countMap.put(a, 1);
            } else {
                countMap.put(a, count+1);
            }
        }
        int q = sc.nextInt();
        for (int i=0; i<q; i++) {
            int b = sc.nextInt();
            int c = sc.nextInt();

            long diffSum  = c-b;
            Integer fromCount = countMap.get(b);
            if (fromCount != null) {
                sum = sum + diffSum * fromCount;
                countMap.remove(b);
                Integer toCount = countMap.get(c);
                if (toCount == null) {
                    countMap.put(c, fromCount);
                } else {
                    countMap.put(c, toCount + fromCount);
                }
            }
            System.out.println(sum);
        }
    }
}