Little penguin Polo adores integer segments, that is, pairs of integers [l; r] (l ≤ r). 

He has a set that consists of n integer segments: [l1; r1], [l2; r2], ..., [ln; rn]. We know that no two segments of this set intersect. In one move Polo can either widen any segment of the set 1 unit to the left or 1 unit to the right, that is transform [l; r] to either segment [l - 1; r], or to segment [l; r + 1].

The value of a set of segments that consists of n segments [l1; r1], [l2; r2], ..., [ln; rn] is the number of integers x, such that there is integer j, for which the following inequality holds, lj ≤ x ≤ rj.

Find the minimum number of moves needed to make the value of the set of Polo's segments divisible by k.

Input

The first line contains two integers n and k (1 ≤ n, k ≤ 105). Each of the following n lines contain a segment as a pair of integers li and ri ( - 105 ≤ li ≤ ri ≤ 105), separated by a space.

It is guaranteed that no two segments intersect. In other words, for any two integers i, j (1 ≤ i < j ≤ n) the following inequality holds, min(ri, rj) < max(li, lj).

Output

In a single line print a single integer — the answer to the problem.

Examples

Input

2 3
1 2
3 4


Output

2


Input

3 7
1 2
3 3
4 7


Output

0
import java.io.*;

public class POLOSEG {

    /**
     * @param args
     */
    public static void main(String[] args) {
        try
        {
            BufferedReader br=new BufferedReader(new InputStreamReader(System.in));
            //BufferedReader br=new BufferedReader(new FileReader("C:/Users/MINTOO/Desktop/Programs/Java/POLOSEG.txt"));
            
            String s[]=br.readLine().split(" ");
            int n=Integer.parseInt(s[0]);
            int k=Integer.parseInt(s[1]);
            
            int i=0,count=0;
            int l,r;
            
            for(i=0;i<n;++i)
            {
                String s2[]=br.readLine().split(" ");
                l=Integer.parseInt(s2[0]);
                r=Integer.parseInt(s2[1]);
                
                count+=r-l+1;
            }
            
            if(count%k==0)
            {
                System.out.println("0");
            }
            else
            {
                System.out.println(k-(count%k));
            }
            
        }
        
        catch(Exception e)
        {
            e.printStackTrace();
        }
    }

}
