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.*;
import java.util.*;

public class Main {
    public static void main(String args[]) throws FileNotFoundException, IOException {
        boolean oj = System.getProperty("ONLINE_JUDGE") != null;
        InputReader in = oj ? new InputReader(System.in) : 
                new InputReader("test.in");
        PrintWriter out = oj ? new PrintWriter(System.out) : 
                new PrintWriter(new FileWriter("test.out"));
        Task t = new Task();
        t.solve(in, out);
        out.close();
    }
}

class Task {
    public void solve(InputReader in, PrintWriter out) {
        int n = in.nextInt();
        int k = in.nextInt();
        int sum = 0;
        for(int i = 0; i < n; ++i)
        {
            int l = in.nextInt();
            int r = in.nextInt();
            sum += r - l + 1;
        }
        int q = 0;
        while(sum % k != 0) 
        {
            ++q;
            ++sum;
        }
        out.println(q);
    }
}

class InputReader
{
    public StringTokenizer tokenizer;
    public BufferedReader reader;
    public InputReader(InputStream stream) {
        reader = new BufferedReader(new InputStreamReader(stream));
        tokenizer = null;
    }
    InputReader(String fileName) throws FileNotFoundException {
        reader = new BufferedReader(new FileReader(fileName));
        tokenizer = null;
    }
    public String next() {
        while(tokenizer == null || !tokenizer.hasMoreTokens()) {
            try {
                tokenizer = new StringTokenizer(reader.readLine());
            }
            catch(IOException ex) {
                throw new RuntimeException();
            }
        }
        return tokenizer.nextToken();
    }
    public int nextInt() {
        return Integer.parseInt(next());
    }
    public double nextDouble() {
        return Double.parseDouble(next());
    }
    public long nextLong() {
        return Long.parseLong(next());
    }
}