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.io.OutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.BufferedWriter;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.UncheckedIOException;
import java.util.Objects;
import java.nio.charset.Charset;
import java.util.StringTokenizer;
import java.io.Writer;
import java.io.OutputStreamWriter;
import java.io.BufferedReader;
import java.util.Comparator;
import java.io.InputStream;

/**
 * Built using CHelper plug-in
 * Actual solution is at the top
 *
 * @author mikit
 */
public class Main {
    public static void main(String[] args) {
        InputStream inputStream = System.in;
        OutputStream outputStream = System.out;
        LightScanner in = new LightScanner(inputStream);
        LightWriter out = new LightWriter(outputStream);
        DStasAndTheQueueAtTheBuffet solver = new DStasAndTheQueueAtTheBuffet();
        solver.solve(1, in, out);
        out.close();
    }

    static class DStasAndTheQueueAtTheBuffet {
        public void solve(int testNumber, LightScanner in, LightWriter out) {
            // out.setBoolLabel(LightWriter.BoolLabel.YES_NO_FIRST_UP)
            int n = in.ints();
            Vec2l[] people = new Vec2l[n];
            for (int i = 0; i < n; i++) {
                people[i] = new Vec2l(in.longs(), in.longs());
            }
            IntroSort.sort(people, Comparator.comparing(v -> -(v.x - v.y)));
            long ans = 0;
            for (int i = 0; i < n; i++) {
                ans += people[i].x * i + people[i].y * (n - i - 1);
            }
            out.ansln(ans);
        }

    }

    static interface Verified {
    }

    static class IntroSort {
        private static int INSERTIONSORT_THRESHOLD = 16;

        private IntroSort() {
        }

        static <T> void sort(T[] a, int low, int high, int maxDepth, Comparator<T> comparator) {
            while (high - low > INSERTIONSORT_THRESHOLD) {
                if (maxDepth-- == 0) {
                    HeapSort.sort(a, low, high, comparator);
                    return;
                }
                int cut = QuickSort.step(a, low, high, comparator);
                sort(a, cut, high, maxDepth, comparator);
                high = cut;
            }
            InsertionSort.sort(a, low, high, comparator);
        }

        public static <T> void sort(T[] a, Comparator<T> comparator) {
            if (a.length <= INSERTIONSORT_THRESHOLD) {
                InsertionSort.sort(a, 0, a.length, comparator);
            } else {
                sort(a, 0, a.length, 2 * BitMath.msb(a.length), comparator);
            }
        }

    }

    static class QuickSort {
        private QuickSort() {
        }

        private static <T> void med(T[] a, int low, int x, int y, int z, Comparator<? super T> comparator) {
            if (comparator.compare(a[z], a[x]) < 0) {
                ArrayUtil.swap(a, low, x);
            } else if (comparator.compare(a[y], a[z]) < 0) {
                ArrayUtil.swap(a, low, y);
            } else {
                ArrayUtil.swap(a, low, z);
            }
        }

        static <T> int step(T[] a, int low, int high, Comparator<? super T> comparator) {
            int x = low + 1, y = low + (high - low) / 2, z = high - 1;
            if (comparator.compare(a[x], a[y]) < 0) {
                med(a, low, x, y, z, comparator);
            } else {
                med(a, low, y, x, z, comparator);
            }

            int lb = low + 1, ub = high;
            while (true) {
                while (comparator.compare(a[lb], a[low]) < 0) {
                    lb++;
                }
                ub--;
                while (comparator.compare(a[low], a[ub]) < 0) {
                    ub--;
                }
                if (lb >= ub) {
                    return lb;
                }
                ArrayUtil.swap(a, lb, ub);
                lb++;
            }
        }

    }

    static class LightScanner {
        private BufferedReader reader = null;
        private StringTokenizer tokenizer = null;

        public LightScanner(InputStream in) {
            reader = new BufferedReader(new InputStreamReader(in));
        }

        public String string() {
            if (tokenizer == null || !tokenizer.hasMoreTokens()) {
                try {
                    tokenizer = new StringTokenizer(reader.readLine());
                } catch (IOException e) {
                    throw new UncheckedIOException(e);
                }
            }
            return tokenizer.nextToken();
        }

        public int ints() {
            return Integer.parseInt(string());
        }

        public long longs() {
            return Long.parseLong(string());
        }

    }

    static class HeapSort {
        private HeapSort() {
        }

        private static <T> void heapfy(T[] a, int low, int high, int i, T val, Comparator<? super T> comparator) {
            int child = 2 * i - low + 1;
            while (child < high) {
                if (child + 1 < high && comparator.compare(a[child], a[child + 1]) < 0) {
                    child++;
                }
                if (comparator.compare(val, a[child]) >= 0) {
                    break;
                }
                a[i] = a[child];
                i = child;
                child = 2 * i - low + 1;
            }
            a[i] = val;
        }

        static <T> void sort(T[] a, int low, int high, Comparator<T> comparator) {
            for (int p = (high + low) / 2 - 1; p >= low; p--) {
                heapfy(a, low, high, p, a[p], comparator);
            }
            while (high > low) {
                high--;
                T pval = a[high];
                a[high] = a[low];
                heapfy(a, low, high, low, pval, comparator);
            }
        }

    }

    static class LightWriter implements AutoCloseable {
        private final Writer out;
        private boolean autoflush = false;
        private boolean breaked = true;

        public LightWriter(Writer out) {
            this.out = out;
        }

        public LightWriter(OutputStream out) {
            this(new BufferedWriter(new OutputStreamWriter(out, Charset.defaultCharset())));
        }

        public LightWriter print(char c) {
            try {
                out.write(c);
                breaked = false;
            } catch (IOException ex) {
                throw new UncheckedIOException(ex);
            }
            return this;
        }

        public LightWriter print(String s) {
            try {
                out.write(s, 0, s.length());
                breaked = false;
            } catch (IOException ex) {
                throw new UncheckedIOException(ex);
            }
            return this;
        }

        public LightWriter ans(String s) {
            if (!breaked) {
                print(' ');
            }
            return print(s);
        }

        public LightWriter ans(long l) {
            return ans(Long.toString(l));
        }

        public LightWriter ansln(long... n) {
            for (long n1 : n) {
                ans(n1).ln();
            }
            return this;
        }

        public LightWriter ln() {
            print(System.lineSeparator());
            breaked = true;
            if (autoflush) {
                try {
                    out.flush();
                } catch (IOException ex) {
                    throw new UncheckedIOException(ex);
                }
            }
            return this;
        }

        public void close() {
            try {
                out.close();
            } catch (IOException ex) {
                throw new UncheckedIOException(ex);
            }
        }

    }

    static final class ArrayUtil {
        private ArrayUtil() {
        }

        public static <T> void swap(T[] a, int x, int y) {
            T t = a[x];
            a[x] = a[y];
            a[y] = t;
        }

    }

    static class InsertionSort {
        private InsertionSort() {
        }

        static <T> void sort(T[] a, int low, int high, Comparator<? super T> comparator) {
            for (int i = low; i < high; i++) {
                for (int j = i; j > low && comparator.compare(a[j - 1], a[j]) > 0; j--) {
                    ArrayUtil.swap(a, j - 1, j);
                }
            }
        }

    }

    static final class BitMath {
        private BitMath() {
        }

        public static int count(int v) {
            v = (v & 0x55555555) + ((v >> 1) & 0x55555555);
            v = (v & 0x33333333) + ((v >> 2) & 0x33333333);
            v = (v & 0x0f0f0f0f) + ((v >> 4) & 0x0f0f0f0f);
            v = (v & 0x00ff00ff) + ((v >> 8) & 0x00ff00ff);
            v = (v & 0x0000ffff) + ((v >> 16) & 0x0000ffff);
            return v;
        }

        public static int msb(int v) {
            if (v == 0) {
                throw new IllegalArgumentException("Bit not found");
            }
            v |= (v >> 1);
            v |= (v >> 2);
            v |= (v >> 4);
            v |= (v >> 8);
            v |= (v >> 16);
            return count(v) - 1;
        }

    }

    static class Vec2l implements Comparable<Vec2l> {
        public long x;
        public long y;

        public Vec2l(long x, long y) {
            this.x = x;
            this.y = y;
        }

        public boolean equals(Object o) {
            if (this == o) return true;
            if (o == null || getClass() != o.getClass()) return false;
            Vec2l vec2i = (Vec2l) o;
            return x == vec2i.x &&
                    y == vec2i.y;
        }

        public int hashCode() {
            return Objects.hash(x, y);
        }

        public String toString() {
            return "(" + x + ", " + y + ")";
        }

        public int compareTo(Vec2l o) {
            if (x == o.x) {
                return Long.compare(y, o.y);
            }
            return Long.compare(x, o.x);
        }

    }
}

