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: Accepted)


import java.text.DecimalFormat;
import java.util.stream.LongStream;
import java.util.stream.IntStream;
import java.io.*;
import java.util.*;

public class Main {

    public static void main(String[] args) {
        FastScanner sc = new FastScanner();
        PrintWriter out = new PrintWriter(System.out);

        AtCoder problem = new AtCoder(sc);
        problem.solve(out);

        out.flush();
    }

}

class AtCoder {

    int N, Q;
    int[] A, B, C;

    AtCoder(FastScanner sc) {
        N = sc.nextInt();
        A = sc.arrayInt(N);
        Q = sc.nextInt();
        B = new int[Q];
        C = new int[Q];
        for (int i = 0; i < Q; i++) {
            B[i] = sc.nextInt();
            C[i] = sc.nextInt();
        }
    }

    void solve(PrintWriter out) {
        int[] cnt = new int[(int) 1e5 + 1];
        long sum = 0;
        for (int a : A) {
            cnt[a]++;
            sum += a;
        }
        for (int i = 0; i < Q; i++) {
            int b = B[i];
            int c = C[i];
            int cnt_b = cnt[b];
            int cnt_c = cnt[c];
            sum += (long) (c - b) * (long) cnt_b;
            out.println(sum);
            cnt[b] = 0;
            cnt[c] = cnt_b + cnt_c;
        }
    }

}

class FastScanner {

    private final InputStream in = System.in;
    private final byte[] buffer = new byte[1024];
    private int ptr = 0;
    private int buflen = 0;

    private boolean hasNextByte() {
        if (ptr < buflen) {
            return true;
        } else {
            ptr = 0;
            try {
                buflen = in.read(buffer);
            } catch (IOException e) {
                e.printStackTrace();
            }
            if (buflen <= 0) {
                return false;
            }
        }
        return true;
    }

    private int readByte() {
        if (hasNextByte()) {
            return buffer[ptr++];
        } else {
            return -1;
        }
    }

    private static boolean isPrintableChar(int c) {
        return 33 <= c && c <= 126;
    }

    public boolean hasNext() {
        while (hasNextByte() && !isPrintableChar(buffer[ptr])) {
            ptr++;
        }
        return hasNextByte();
    }

    public String next() {
        if (!hasNext()) {
            throw new NoSuchElementException();
        }
        StringBuilder sb = new StringBuilder();
        int b = readByte();
        while (isPrintableChar(b)) {
            sb.appendCodePoint(b);
            b = readByte();
        }
        return sb.toString();
    }

    public long nextLong() {
        if (!hasNext()) {
            throw new NoSuchElementException();
        }
        long n = 0;
        boolean minus = false;
        int b = readByte();
        if (b == '-') {
            minus = true;
            b = readByte();
        }
        if (b < '0' || '9' < b) {
            throw new NumberFormatException();
        }
        while (true) {
            if ('0' <= b && b <= '9') {
                n *= 10;
                n += b - '0';
            } else if (b == -1 || !isPrintableChar(b)) {
                return minus ? -n : n;
            } else {
                throw new NumberFormatException();
            }
            b = readByte();
        }
    }

    public int nextInt() {
        long nl = nextLong();
        if (nl < Integer.MIN_VALUE || nl > Integer.MAX_VALUE) {
            throw new NumberFormatException();
        }
        return (int) nl;
    }

    public double nextDouble() {
        return Double.parseDouble(next());
    }

    public int[] arrayInt(int N) {
        int[] array = new int[N];
        for (int i = 0; i < N; i++) {
            array[i] = nextInt();
        }
        return array;
    }

    public long[] arrayLong(int N) {
        long[] array = new long[N];
        for (int i = 0; i < N; i++) {
            array[i] = nextLong();
        }
        return array;
    }

    public double[] arrayDouble(int N) {
        double[] array = new double[N];
        for (int i = 0; i < N; i++) {
            array[i] = nextDouble();
        }
        return array;
    }

    public String[] arrayString(int N) {
        String[] array = new String[N];
        for (int i = 0; i < N; i++) {
            array[i] = next();
        }
        return array;
    }
}

class My {

    static void ans(boolean b) {
        System.out.println(b ? "Yes" : "No");
    }

    static void ANS(boolean b) {
        System.out.println(b ? "YES" : "NO");
    }

    static String sort(String s) {
        char[] ch = s.toCharArray();
        Arrays.sort(ch);
        return String.valueOf(ch);
    }

    static String reverse(String s) {
        return new StringBuilder(s).reverse().toString();
    }

    static int[] reverse(int[] array) {
        for (int i = 0; i < array.length / 2; i++) {
            int temp = array[i];
            array[i] = array[array.length - 1 - i];
            array[array.length - 1 - i] = temp;
        }
        return array;
    }

    static long[] reverse(long[] array) {
        for (int i = 0; i < array.length / 2; i++) {
            long temp = array[i];
            array[i] = array[array.length - 1 - i];
            array[array.length - 1 - i] = temp;
        }
        return array;
    }

    static double[] reverse(double[] array) {
        for (int i = 0; i < array.length / 2; i++) {
            double temp = array[i];
            array[i] = array[array.length - 1 - i];
            array[array.length - 1 - i] = temp;
        }
        return array;
    }

    static String[] reverse(String[] array) {
        for (int i = 0; i < array.length / 2; i++) {
            String temp = array[i];
            array[i] = array[array.length - 1 - i];
            array[array.length - 1 - i] = temp;
        }
        return array;
    }

    static char[] reverse(char[] array) {
        for (int i = 0; i < array.length / 2; i++) {
            char temp = array[i];
            array[i] = array[array.length - 1 - i];
            array[array.length - 1 - i] = temp;
        }
        return array;
    }

    static long min(long... numbers) {
        Arrays.sort(numbers);
        return numbers[0];
    }

    static int min(int... numbers) {
        Arrays.sort(numbers);
        return numbers[0];
    }

    static double min(double... numbers) {
        Arrays.sort(numbers);
        return numbers[0];
    }

    static long max(long... numbers) {
        Arrays.sort(numbers);
        return numbers[numbers.length - 1];
    }

    static int max(int... numbers) {
        Arrays.sort(numbers);
        return numbers[numbers.length - 1];
    }

    static double max(double... numbers) {
        Arrays.sort(numbers);
        return numbers[numbers.length - 1];
    }

    static int sum(long number) {
        int sum = 0;
        while (number > 0) {
            sum += number % 10;
            number /= 10;
        }
        return sum;
    }

}