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.
"""
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 \____\___/ \__,_|\___|_|  \___/|_|  \___\___||___/

"""
"""
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"""

import sys
import math
import collections
import operator as op
from collections import deque
from math import gcd
#sys.stdin = open('input.txt', 'r')
#sys.stdout = open('output.txt', 'w')

from functools import reduce
from sys import stdin, stdout


def ncr(n, r):
    r = cn(r, n - r)
    numer = reduce(op.mul, range(n, n - r, -1), 1)
    denom = reduce(op.mul, range(1, r + 1), 1)
    return numer // denom  # or / in Python 2


def isPowerOfTwo(x):
    return (x and (not(x & (x - 1))))


def factors(n):
    return list(set(reduce(list.__add__, ([i, n // i] for i in range(1, int(n**0.5) + 1) if n % i == 0))))

T = 1
T = int(stdin.readline())
for _ in range(T):
    # s = str(stdin.readline().strip('\n'))
    # a, b = list(map(int, stdin.readline().split()))
    # s = list(stdin.readline().strip('\n'))
    # b = list(stdin.readline().strip('\n'))
    #n = int(stdin.readline())
    n, x, m = list(map(int, stdin.readline().split()))
    # n = list(map(int, stdin.readline().split()))
    #a = list(map(int, stdin.readline().split()))
    d = {}
    c, d = x, x
    for i in range(m):

        l, r = list(map(int, stdin.readline().rstrip().split()))

        if(x <= r and x >= l):
            if(c > l):
                c = l
            if(d < r):
                d = r
        else:
            if((r >= c and r <= d) or (l >= c and l <= d)):
                if(c > l):
                    c = l
                if(d < r):
                    d = r
    ans = d - c + 1
    print(ans)
