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.
t = int(input())

def solve(n, x, m, ops, coords):
    coords = sorted(set(coords + [0] + [x] + [x + 1] + [n]))
    compress = {v: i for i, v in enumerate(coords)}
    decompress = {i: v for i, v in enumerate(coords)}
    intervals = [0] * (len(coords) - 1)
    intervals[compress[x]] = 1
    for l, r in ops:
        has1 = False
        for i in range(len(coords) - 1):
            if compress[l] <= i and compress[r + 1] >= i + 1:
                if intervals[i] == 1:
                    has1 = True
                    break
        if has1:
            for i in range(len(coords) - 1):
                if compress[l] <= i and compress[r + 1] >= i + 1:
                    intervals[i] = 1
    cnt = 0
    for i in range(len(coords) - 1):
        if intervals[i]:
            cnt += decompress[i + 1] - decompress[i]
    return cnt


for _ in range(t):
    n, x, m = map(int, input().split())
    x -= 1
    operations = []
    points = []
    for _ in range(m):
        l, r = map(int, input().split())
        l -= 1
        r -= 1
        points.append(l)
        points.append(r + 1)
        operations.append((l, r))
    print(solve(n, x, m, operations, points))
