You are given an array consisting of n integers a_1, a_2, ..., a_n. Initially a_x = 1, all other elements are equal to 0.

You have to perform m operations. During the i-th operation, you choose two indices c and d such that l_i ≤ c, d ≤ r_i, and swap a_c and a_d.

Calculate the number of indices k such that it is possible to choose the operations so that a_k = 1 in the end.

Input

The first line contains a single integer t (1 ≤ t ≤ 100) — the number of test cases. Then the description of t testcases follow.

The first line of each test case contains three integers n, x and m (1 ≤ n ≤ 10^9; 1 ≤ m ≤ 100; 1 ≤ x ≤ n).

Each of next m lines contains the descriptions of the operations; the i-th line contains two integers l_i and r_i (1 ≤ l_i ≤ r_i ≤ n).

Output

For each test case print one integer — the number of indices k such that it is possible to choose the operations so that a_k = 1 in the end.

Example

Input


3
6 4 3
1 6
2 3
5 5
4 1 2
2 4
1 2
3 3 2
2 3
1 2


Output


6
2
3

Note

In the first test case, it is possible to achieve a_k = 1 for every k. To do so, you may use the following operations:

  1. swap a_k and a_4; 
  2. swap a_2 and a_2; 
  3. swap a_5 and a_5. 



In the second test case, only k = 1 and k = 2 are possible answers. To achieve a_1 = 1, you have to swap a_1 and a_1 during the second operation. To achieve a_2 = 1, you have to swap a_1 and a_2 during the second operation.
import java.io.*;
import java.util.*;
 
 
public class Main{
static int mod = (int)(Math.pow(10, 9) + 7);
   public static void main(String[] args) {
      MyScanner sc = new MyScanner();
      out = new PrintWriter(new BufferedOutputStream(System.out));
      int t=  sc.nextInt();
      while (t-->0) {
    	  int n = sc.nextInt();
          int x = sc.nextInt();
          int m = sc.nextInt();
            int start = x;
            int end = x;
            
            for (int i = 0; i < m; i++){
                int a = sc.nextInt();
                int b = sc.nextInt();
                
                if (start >= a && b >= start){
                    start = a;
                }
                if (end <= b && end >= a) end = b;
               // out.println(start + " " + end);
            }

            out.println(end - start + 1);
            
      }
      
      out.close();
   }
   static class Pair implements Comparable<Pair>{
       int index;
       boolean start;
       int n;
       public Pair(int i, boolean s, int num){
           index = i;
           start = s;
           n = num;
       }
       public int compareTo(Pair o){
           if (index == o.index){
               return start ? -1: 1;
           }
           return index - o.index;
       }
   }
   
   static long pow(long a, long N) {
	   if (N == 0) return 1;
	   else if (N == 1) return a;
	   else {
		   long R = pow(a,N/2);
		   if (N % 2 == 0) {
			   return R*R;
		   }
		   else {
			   return R*R*a;
		   }
	   }
   }
   
   static long powMod(long a, long N) {
	   if (N == 0) return 1;
	   else if (N == 1) return a % mod;
	   else {
		   long R = powMod(a,N/2) % mod;
		   R *= R % mod;
		   if (N % 2 == 1) {
			   R *= a % mod;
		   }
			   return R % mod;
	   }
   }
static void mergeSort(int[] A){ // low to hi sort, single array only
      int n = A.length;
      if (n < 2) return;
      int[] l = new int[n/2];
      int[] r = new int[n - n/2];
 
      for (int i = 0; i < n/2; i++){
        l[i] = A[i];
      }
 
      for (int j = n/2; j < n; j++){
        r[j-n/2] = A[j];
      }
 
      mergeSort(l);
      mergeSort(r);
      merge(l, r, A);
    }
 
    static void merge(int[] l, int[] r, int[] a){
      int i = 0, j = 0, k = 0;
      while (i < l.length && j < r.length && k < a.length){
        if (l[i] < r[j]){
          a[k] = l[i];
          i++;
        }
        else{
          a[k] = r[j];
          j++;
        }
        k++;
      }
      while (i < l.length){
        a[k] = l[i];
        i++;
        k++;
      }
 
      while (j < r.length){
        a[k] = r[j];
        j++;
        k++;
      }
    }

   

   //-----------PrintWriter for faster output---------------------------------
   public static PrintWriter out;
      
   //-----------MyScanner class for faster input----------
   public static class MyScanner {
      BufferedReader br;
      StringTokenizer st;
 
      public MyScanner() {
         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;
      }

   }
   //--------------------------------------------------------
}





