N one dimensional kingdoms are represented as intervals of the form [ai , bi] on the real line.
A kingdom of the form [L, R] can be destroyed completely by placing a bomb at a point x on the real line if L
≤ x ≤ R.


Your task is to determine minimum number of bombs required to destroy all the one dimensional kingdoms.

Input


First line of the input contains T denoting number of test cases.


For each test case, first line contains N denoting the number of one dimensional kingdoms.


For each next N lines, each line contains two space separated integers ai and bi.



Output
For each test case , output an integer denoting the minimum  number of bombs required.

Constraints
Example
Input:
1
3
1 3
2 5
6 9

Output:
2

Explanation
There are three kingdoms [1,3] ,[2,5] and [6,9]. You will need at least 2 bombs
to destroy the kingdoms. In one of the possible solutions, you can place two bombs at x = 2 and x = 6 .
t = int(raw_input())
for case in range(t):
    n = int(raw_input())
    arr = [map(int, raw_input().split()) for x in range(n)]
    arr.sort(key=lambda x:x[1])
    r = arr[0][1]
    ans = 1
    for i in range(1, n):
        if arr[i][0] > r:
            ans += 1
            r = arr[i][1]
        else:
            r = min(r, arr[i][1])
    print ans