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.util.*;
import java.lang.*;
import java.math.*;
import java.io.*;
import java.util.HashSet;
import java.util.Scanner;
import java.util.Set;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Arrays;
import java.util.HashMap;
import java.util.Map;
import java.text.DecimalFormat;
import java.lang.Math;
import java.util.Iterator; 
import java.util.TreeSet;
public class B1366{
    static int pInf = Integer.MAX_VALUE;
    static int nInf = Integer.MIN_VALUE;
    public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		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 p = sc.nextInt();
		        int q = sc.nextInt();
		        if(q<l || r<p){
		            continue;
		        }
		        l = Math.min(l,p);
		        r = Math.max(r,q);
		    }
		    System.out.println(r-l+1);
		}
	}
	public static int ffloor(int[] b, long ele){
	    int s = 0;
	    int e = b.length-1;
	    while(s<=e){
	        int m = s+(e-s)/2;
	        if(b[m] == ele){
	            return b[m];
	        }
	        else if(b[m]>ele){
	            e = m-1;
	        }
	        else{
	            s = m+1;
	        }
	    }
	    return b[e];
	}
	public static int cceil(int[] a, long ele){
	    int s = 0;
	    int e = a.length-1;
	    while(s<=e){
	        int m = s+(e-s)/2;
	        if(a[m] == ele){
	            return a[m];
	        }
	        else if(a[m]>ele){
	            e = m-1;
	        }
	        else{
	            s = m+1;
	        }
	    }
	    return a[s];
	}
	public static int floor(ArrayList<Pair> A , long ele){
	    int s = 0;
	    int e = A.size()-1;
	    while(s<=e){
	        int m = s+(e-s)/2;
	        if(A.get(m).x == ele){
	            return A.get(m).x;
	        }
	        else if(A.get(m).x>ele){
	            e = m-1;
	        }
	        else{
	            s = m+1;
	        }
	    }
	    return A.get(e).x;
	}
	public static int ceil(Pair[] a, long ele){
	    int s = 0;
	    int e = a.length-1;
	    while(s<=e){
	        int m = s+(e-s)/2;
	        if(a[m].x == ele){
	            a[m].y = 1;
	            return a[m].x;
	        }
	        else if(a[m].x>ele){
	            e = m-1;
	        }
	        else{
	            s = m+1;
	        }
	    }
	    a[s].y = 1;
	    return a[s].x;
	}
	////////////////////////////////////////////////////////////////////////////////
	static class Pair implements Comparable<Pair>{
		int x;
		int y;
		public Pair(int x, int y) {
			this.x = x;
			this.y = y;
		}
		@Override
		public int compareTo(Pair o) {
			// TODO Auto-generated method stub
			if(this.x==o.x){
			    return (this.y-o.y);
			}
			return (this.x-o.x);
		}
	}
	public static boolean isPrime(int n){
	    if(n < 2){
	        return false;
	    }
	    if(n%2==0){
	        return n==2;
	    }
	    if(n%3==0){
	        return n==3;
	    }
	    int i = 5;
	    int h = (int)Math.floor(Math.sqrt(n)+1);
	    while(i <= h){
	        if(n%i==0){
	            return false;
	        }
	        if(n%(i+2)==0){
	            return false;
	        }
	        i += 6;
	    }
	    return true;
	}
	public static long gcd(long a, long b){
	    return b==0? a:gcd(b, a%b);
	}
	public static long bSearch(int n,ArrayList<Long> A){
	    int s = 0;
	    int e = A.size()-1;
	    while(s<=e){
	        int m = s+(e-s)/2;
	        if(A.get(m)==(long)n){
	            return A.get(m);
	        }
	        else if(A.get(m)>(long)n){
	            e = m-1;
	        }
	        else{
	            s = m+1;
	        }
	    }
	    return A.get(s);
	}
	static class Point implements Comparable<Point>{
		int x;
		int y;
		public Point(int x, int y){
			this.x = x;
			this.y = y;
		}
		@Override
		public int compareTo(Point o) {
			// TODO Auto-generated method stub
			if(this.x==o.x){
			    return this.y-o.y;
			}
			return this.x-o.x;
		}
	}
	public static long[] fact;
	public static final long modulo = 1000000007;
	public static long modinv(long x){
	    return modpow(x, modulo-2);
	}
	public static long modpow(long a, long b){
	    if(b==0){
	        return 1;
	    }
	    long x = modpow(a, b/2);
	    x = (x*x)%modulo;
	    if(b%2==1){
	        return (x*a)%modulo;
	    }
	    return x;
	}
}