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.BufferedReader;
import java.io.FileReader;
import java.io.IOException; 
import java.io.InputStreamReader; 
import java.util.Scanner; 
import java.util.StringTokenizer; 
import java.util.*;
import java.io.*;
public class codeforces 
{ 
   static class Student{
       int x,y;
        Student(int x,int y){
            this.x=x;
            this.y=y;
            //this.z=z;
        }
    }
    static int prime[];
    static void sieveOfEratosthenes(int n) 
    { 
        // Create a boolean array "prime[0..n]" and initialize 
        // all entries it as true. A value in prime[i] will 
        // finally be false if i is Not a prime, else true. 
        int pos=0;
        prime= new int[n+1]; 
        for(int p = 2; p*p <=n; p++) 
        { 
            // If prime[p] is not changed, then it is a prime 
            if(prime[p] == 0)
            { 
                // Update all multiples of p
                prime[p]=p;
                for(int i = p*p; i <= n; i += p) 
                    prime[i] = p; 
            } 
        } 
    }
static    class Sortbyroll implements Comparator<Student> 
{ 
    // Used for sorting in ascending order of 
    // roll number 
    public int compare(Student c, Student b) 
    { 
        if(c.x<b.x)
            return -1;
        if(c.x>b.x)
            return 1;
        return c.y-b.y;
    } 
} 
static class FastReader 
    { 
        BufferedReader br; 
        StringTokenizer st; 
  
        public FastReader() 
        { 
            br = new BufferedReader(new
                     InputStreamReader(System.in)); 
        } 
  
        String next() 
        { 
            while (st == null || !st.hasMoreElements()) 
            { 
                try
                { 
                    st = new StringTokenizer(br.readLine()); 
                } 
                catch (IOException  e) 
                { 
                    e.printStackTrace(); 
                } 
            } 
            return st.nextToken(); 
        } 
  
        int nextInt() 
        { 
            return Integer.parseInt(next()); 
        } 
  
        long nextLong() 
        { 
            return Long.parseLong(next()); 
        } 
  
        double nextDouble() 
        { 
            return Double.parseDouble(next()); 
        } 
  
        String nextLine() 
        { 
            String str = ""; 
            try
            { 
                str = br.readLine(); 
            } 
            catch (IOException e) 
            { 
                e.printStackTrace(); 
            } 
            return str; 
        } 
    } 
 
    static class Edge{
        int a,b;
        Edge(int a,int b){
            this.a=a;
            this.b=b;
        }
    }
    static class Trie{
        HashMap<Character,Trie>map;
         int c;
        Trie(){
            map=new HashMap<>();
            //z=null;
            //o=null;
            c=0;
        }
    }
    //static long ans;
    static int parent[];
    static int rank[];
    static int b[][];
    static int bo[];
    static int ho[];
    static int seg[];
    //static int pos;
   // static long mod=1000000007;
    //static int dp[][];
    static HashMap<Integer,Integer>map;
    static PriorityQueue<Student>q=new PriorityQueue<>();
    //static Stack<Integer>st;
   // static ArrayList<Character>ans;
    static ArrayList<ArrayList<Integer>>adj;
    static long ans;
    static Trie root;
    static long fac[];
    static long mod=(long)(1000000007);
    //static int ans;
    static void solve()throws IOException{
        FastReader sc=new FastReader();
        int n,i,x,y;
        n=sc.nextInt();
        int a[]=new int[n];
        for(i=0;i<n;i++){
            x=sc.nextInt();
            y=sc.nextInt();
            ans+=-(long)x+(long)y*(long)n;
            a[i]=x-y;
        }
        Arrays.sort(a);
        for(i=0;i<n;i++){
            ans+=(long)(n-i)*(long)a[i];
        }
        System.out.println(ans);
    }
    static void build(StringBuilder sb,int n,char a){
        if(n==0)
        {
            sb.append(a);
            return;
        }
        int x=(int)Math.sqrt(2*n);
        if(x*(x+1)>2*n)
            x-=1;
        for(int i=0;i<=x;i++)
            sb.append(a);
        n-=(x*(x+1))/2;
        build(sb,n,(char)((int)a+1));
    }
    static void dfs(Trie root,int k){
        if(root==null)
            return;
        for(char i='A';i<='Z';i++){
            if(root.map.containsKey(i)){
                ans+=root.map.get(i).c/k;
                dfs(root.map.get(i),k);
            }
        }
    }
    static long nCr(long n, long r, 
                                    long p) 
    { 
        return (fac[(int)n]* modInverse(fac[(int)r], p) 
                % p * modInverse(fac[(int)(n-r)], p) 
                                    % p) % p; 
    } 
    //static int prime[];
    //static int dp[];
    public static void main(String[] args){
        //long sum=0;
        try {
                codeforces.solve();
                } catch (Exception e) {
                    e.printStackTrace();
                }
    }
       static long modInverse(long n, long p) 
    { 
        return power(n, p-(long)2,p); 
    } 
 static long power(long x, long y, long p) 
{ 
    long res = 1;      // Initialize result 
  
    x = x % p;  // Update x if it is more than or  
                // equal to p 
  
    while (y > 0) 
    { 
        // If y is odd, multiply x with result 
        if (y %(long)2!=0) 
            res = (res*x) % p; 
  
        // y must be even now 
        y = y>>1; // y = y/2 
        x = (x*x) % p;   
    } 
    return res%p;
 }
    /*public static long power(long x,long a) {
		if(a==0) return 1;
		if(a%2==1)return (x*1L*power(x,a-1))%mod;
		return (power((int)((x*1L*x)%mod),a/2))%mod;
	}*/
   static int find(int x) 
    { 
        // Finds the representative of the set 
        // that x is an element of 
        while(parent[x]!=x) 
        { 
            // if x is not the parent of itself 
            // Then x is not the representative of 
            // his set,
            x=parent[x];
  
            // so we recursively call Find on its parent 
            // and move i's node directly under the 
            // representative of this set 
        } 
  
        return x; 
    }
    static void union(int x, int y) 
    { 
        // Find representatives of two sets 
        int xRoot = find(x), yRoot = find(y); 
  
        // Elements are in the same set, no need 
        // to unite anything. 
        if (xRoot == yRoot) 
            return; 
  
         // If x's rank is less than y's rank 
        if (rank[xRoot] < rank[yRoot]) 
  
            // Then move x under y  so that depth 
            // of tree remains less 
            parent[xRoot] = yRoot; 
  
        // Else if y's rank is less than x's rank 
        else if (rank[yRoot] < rank[xRoot]) 
  
            // Then move y under x so that depth of 
            // tree remains less 
            parent[yRoot] = xRoot; 
  
        else // if ranks are the same 
        { 
            // Then move y under x (doesn't matter 
            // which one goes where) 
            parent[yRoot] = xRoot; 
  
            // And increment the the result tree's 
            // rank by 1 
            rank[xRoot] = rank[xRoot] + 1; 
        } 
    } 
    static long gcd(long a, long b) 
    { 
        if (a == 0){ 
             //ans+=b;
            return b;
        }
        return gcd(b % a, a); 
    }
}