During a break in the buffet of the scientific lyceum of the Kingdom of Kremland, there was formed a queue of n high school students numbered from 1 to n. Initially, each student i is on position i. Each student i is characterized by two numbers — a_i and b_i. Dissatisfaction of the person i equals the product of a_i by the number of people standing to the left of his position, add the product b_i by the number of people standing to the right of his position. Formally, the dissatisfaction of the student i, which is on the position j, equals a_i ⋅ (j-1) + b_i ⋅ (n-j).

The director entrusted Stas with the task: rearrange the people in the queue so that minimize the total dissatisfaction.

Although Stas is able to solve such problems, this was not given to him. He turned for help to you.

Input

The first line contains a single integer n (1 ≤ n ≤ 10^5) — the number of people in the queue.

Each of the following n lines contains two integers a_i and b_i (1 ≤ a_i, b_i ≤ 10^8) — the characteristic of the student i, initially on the position i.

Output

Output one integer — minimum total dissatisfaction which can be achieved by rearranging people in the queue.

Examples

Input


3
4 2
2 3
6 1


Output


12

Input


4
2 4
3 3
7 1
2 3


Output


25

Input


10
5 10
12 4
31 45
20 55
30 17
29 30
41 32
7 1
5 5
3 15


Output


1423

Note

In the first example it is optimal to put people in this order: (3, 1, 2). The first person is in the position of 2, then his dissatisfaction will be equal to 4 ⋅ 1+2 ⋅ 1=6. The second person is in the position of 3, his dissatisfaction will be equal to 2 ⋅ 2+3 ⋅ 0=4. The third person is in the position of 1, his dissatisfaction will be equal to 6 ⋅ 0+1 ⋅ 2=2. The total dissatisfaction will be 12.

In the second example, you need to put people in this order: (3, 2, 4, 1). The total dissatisfaction will be 25.
import java.util.*;
import java.io.*;

public class R553D {

    public static void main (String[] args) {
        InputReader in = new InputReader(System.in);      //creating input reader
        PrintWriter w = new PrintWriter(System.out);     //creating writer
        int n = in.nextInt();
        Student[] a = new Student[n];
        long ans = 0;
        for (int i = 0; i < n; i++) {
            a[i] = new Student(i, in.nextInt(), in.nextInt());
            ans += 1L * a[i].b_i * n - a[i].a_i;
        }
        Arrays.sort(a);
        for (int i = 0; i < n; i++) {
            ans += 1L * (a[n - 1 - i].diff * (i + 1));
        }
        w.println(ans);


        w.close();
    }
    static class Student implements Comparable<Student> {
        long ind, a_i, b_i, diff;
        Student(long ind, long a_i, long b_i) {
            this.a_i = a_i;
            this.ind = ind;
            this.b_i = b_i;
            diff = a_i - b_i;
        }
        public int compareTo(Student O) {
            return Long.compare(this.diff, O.diff);
        }
    }
    static int binaryLowerBound(long[] a, long k) {
        int l = -1, r = a.length;
        while (r - l > 1) {
            int mid = (l + r) / 2;
            if (a[mid] == k)
                return mid;
            else if (a[mid] > k)
                r = mid;
            else
                l = mid;
        }
        return l;
    }
    static int findMin(int[] a) {
        int ans = a.length - 1;
        for (int x : a)
            if (x > -1)
                ans = Math.min(ans, x);
        return ans;
    }
    static long pow(long x, long p, long mod) {
        long ans = 1;
        x %= mod;
        while (p > 0) {
            if (p % 2 == 1)
                ans = (ans * x) % mod;
            x = (x * x) % mod;
            p /= 2;
        }
        return ans;
    }
    static boolean nextPermutation(int[] a) {
        int n = a.length;
        int ptr = n - 1;
        while (ptr > 0 && a[ptr - 1] >= a[ptr]) {
            ptr--;
        }

        for (int i = ptr, j = n - 1; i < j; i++, j--) {
            int tmp = a[i];
            a[i] = a[j];
            a[j] = tmp;
        }

        if (ptr == 0) {
            return false;
        }

        for (int i = ptr;; i++) {
            if (a[ptr - 1] < a[i]) {
                int tmp = a[ptr - 1];
                a[ptr - 1] = a[i];
                a[i] = tmp;
                return true;
            }
        }
    }
    static int fibo(int n) {
        if (n == 1 || n == 2)
            return 1;
        return fibo(n - 1) + fibo(n - 2);
    }
    /*static int fibo(int n) {
        if (n == 0)
            return 0;
        if (n == 1 || n == 2)
            return f[n] = 1;
        if (f[n] != 0)
            return f[n];
        if (n % 2 == 0) {
            int k = (n) / 2;
            return f[n] = (fibo(k - 1) * 2 + fibo(k)) * fibo(k);
        } else {
            int k = (n + 1) / 2;
            return f[n] = fibo(k - 1) * fibo(k - 1) + fibo(k) * fibo(k);
        }
    }*/
    static class Edge implements Comparable<Edge> {
        int from, to, cost;
        Edge(int from, int to, int cost) {
            this.from = from;
            this.to = to;
            this.cost = cost;
        }
        public int compareTo(Edge O) {
            return this.cost - O.cost;
        }
    }
    static String swap(String s, int i, int j) {
        char[] ca = s.toCharArray();
        char temp = ca[i];
        ca[i] = ca[j];
        ca[j] = temp;
        return new String(ca);
    }
    static void findMissExtra(int[] a) {
        HashSet<Integer> hs = new HashSet<>();
        int n = a.length, extra = 0, miss = 0;
        for (int i = 0; i < n; i++) {
            if (hs.contains(a[i]))
                extra = a[i];
            hs.add(a[i]);

        }
        for (int i = 1; i <= n; i++) {
            if (!hs.contains(i)) {
                miss = i;
                break;
            }
        }
        System.out.println(miss + ", " + extra);
    }
    static void find(int m, int s) {
        if (s == 0 || s > m * 9) {
            System.out.println("Impossible");
            return ;
        }
        s -= 1;
        int[] num = new int[m];
        for (int i = m - 1; i > 0; i--) {
            int temp = Math.min(s, 9);
            num[i] = temp;
            s -= temp;
        }
        num[0] += s + 1;
        for (int x : num)
            System.out.print(x);
    }
    static class InputReader {
        private InputStream stream;
        private byte[] buf = new byte[1024];
        private int curChar;
        private int numChars;

        public InputReader(InputStream stream) {
            this.stream = stream;
        }

        public int read() {
            if (numChars == -1)
                throw new UnknownError();
            if (curChar >= numChars) {
                curChar = 0;
                try {
                    numChars = stream.read(buf);
                } catch (IOException e) {
                    throw new UnknownError();
                }
                if (numChars <= 0)
                    return -1;
            }
            return buf[curChar++];
        }

        public int peek() {
            if (numChars == -1)
                return -1;
            if (curChar >= numChars) {
                curChar = 0;
                try {
                    numChars = stream.read(buf);
                } catch (IOException e) {
                    return -1;
                }
                if (numChars <= 0)
                    return -1;
            }
            return buf[curChar];
        }

        public void skip(int x) {
            while (x-- > 0)
                read();
        }

        public int nextInt() {
            return Integer.parseInt(next());
        }

        public long nextLong() {
            return Long.parseLong(next());
        }

        public String nextString() {
            return next();
        }

        public String next() {
            int c = read();
            while (isSpaceChar(c))
                c = read();
            StringBuffer res = new StringBuffer();
            do {
                res.appendCodePoint(c);
                c = read();
            } while (!isSpaceChar(c));

            return res.toString();
        }

        public String nextLine() {
            StringBuffer buf = new StringBuffer();
            int c = read();
            while (c != '\n' && c != -1) {
                if (c != '\r')
                    buf.appendCodePoint(c);
                c = read();
            }
            return buf.toString();
        }

        public double nextDouble() {
            int c = read();
            while (isSpaceChar(c))
                c = read();
            int sgn = 1;
            if (c == '-') {
                sgn = -1;
                c = read();
            }
            double res = 0;
            while (!isSpaceChar(c) && c != '.') {
                if (c == 'e' || c == 'E')
                    return res * Math.pow(10, nextInt());
                if (c < '0' || c > '9')
                    throw new InputMismatchException();
                res *= 10;
                res += c - '0';
                c = read();
            }
            if (c == '.') {
                c = read();
                double m = 1;
                while (!isSpaceChar(c)) {
                    if (c == 'e' || c == 'E')
                        return res * Math.pow(10, nextInt());
                    if (c < '0' || c > '9')
                        throw new InputMismatchException();
                    m /= 10;
                    res += (c - '0') * m;
                    c = read();
                }
            }
            return res * sgn;
        }
        public int[] nextIntArray(int n) {
            int[] a = new int[n];
            for (int i = 0; i < n; i++)
                a[i] = nextInt();
            return a;
        }
        public long[] nextLongArray(int n) {
            long[] a = new long[n];
            for (int i = 0; i < n; i++)
                a[i] = nextLong();
            return a;
        }
        public boolean hasNext() {
            int value;
            while (isSpaceChar(value = peek()) && value != -1)
                read();
            return value != -1;
        }

        private boolean isSpaceChar(int c) {
            return c == ' ' || c == '\n' || c == '\r' || c == '\t' || c == -1;
        }

    }
}