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.
// package LeetCode;

import java.util.*;
import java.io.*;

public class Main {

	static class Reader {
		BufferedReader br;
		StringTokenizer st;

		public Reader() {
			br = new BufferedReader(new InputStreamReader(System.in));
		}

		public int nextInt() throws IOException {
			if (st == null || !st.hasMoreTokens()) {
				st = new StringTokenizer(br.readLine());
			}
			return Integer.parseInt(st.nextToken());
		}

		public float nextFloat() throws IOException {
			if (st == null || !st.hasMoreTokens()) {
				st = new StringTokenizer(br.readLine());
			}
			return Float.parseFloat(st.nextToken());
		}

		public long nextLong() throws IOException {
			if (st == null || !st.hasMoreTokens()) {
				st = new StringTokenizer(br.readLine());
			}
			return Long.parseLong(st.nextToken());
		}

		public double nextDouble() throws IOException {
			if (st == null || !st.hasMoreTokens()) {
				st = new StringTokenizer(br.readLine());
			}
			return Double.parseDouble(st.nextToken());
		}

		public String nextLine() throws IOException {
			return br.readLine();
		}

		public String next() throws IOException {
			if (st == null || !st.hasMoreTokens()) {
				st = new StringTokenizer(br.readLine());
			}
			return st.nextToken();
		}
	}

	static class Pair implements Comparable<Pair> {
		int index, val;

		public Pair(int index, int val) {
			this.index = index;
			this.val = val;
		}

		@Override
		public int compareTo(Pair o) {
			return o.val - this.val;
		}
	}

	static int mod = (int) (1e9 + 7);

	public static void main(String[] args) throws IOException {
		Reader sc = new Reader();
		PrintWriter out = new PrintWriter(new BufferedWriter(new OutputStreamWriter(System.out)));
		try {
			int t = sc.nextInt();
			while (t-- > 0) {
				int n = sc.nextInt();
				int x = sc.nextInt();
				int m = sc.nextInt();
				int l = x;
				int r = x;
				for(int i=0;i<m;i++) {
					int a = sc.nextInt();
					int b = sc.nextInt();
					if(b<l || a>r)
						continue;
					if(a<l) {
						l = a;
					}
					if(b>r) {
						r = b;
					}
				}
				out.println(r-l+1);
			}
			out.flush();
		} catch (Exception e) {
			e.printStackTrace();
		}
	}
}
//6
//4
//0 0 1 2
//4
//1 1 2 4
//4
//0 1 3 3
//4
//1 1 3 4
//4
//0 2 2 3
//4
//1 2 2 2

//3 3 0 1 
//-1
//-1
//-1
//1 0 4 2 
//0 1 1 3 
