HDU 1051 Wooden SticksLIS

Description
There is a pile of n wooden sticks. The length and weight of each stick are known in advance. The sticks are to be processed by a 
woodworking machine in one by one fashion. It needs some time, called setup time, for the machine to prepare processing a stick. 
The setup times are associated with cleaning operations and changing tools and shapes in the machine. The setup times of the 
woodworking machine are given as follows: 


(a) The setup time for the first wooden stick is 1 minute. 
(b) Right after processing a stick of length l and weight w , the machine will need no setup time for a stick of length l' and 
weight w' if l<=l' and w<=w'. Otherwise, it will need 1 minute for setup. 


You are to find the minimum setup time to process a given pile of n wooden sticks. For example, if you have five sticks whose pairs 
of length and weight are (4,9), (5,2), (2,1), (3,5), and (1,4), then the minimum setup time should be 2 minutes since there is a
 sequence of pairs (1,4), (3,5), (4,9), (2,1), (5,2). 




Input
The input consists of T test cases. The number of test cases (T) is given in the first line of the input file. Each test case 
consists of two lines: The first line has an integer n , 1<=n<=5000, that represents the number of wooden sticks in the test case,
 and the second line contains n 2 positive integers l1, w1, l2, w2, ..., ln, wn, each of magnitude at most 10000 , where li and wi
  are the length and weight of the i th wooden stick, respectively. The 2n integers are delimited by one or more spaces. 




Output
The output should contain the minimum setup time in minutes, one per line. 




Sample Input
3 
5 
4 9 5 2 2 1 3 5 1 4 
3 
2 2 1 1 2 2 
3 
1 3 2 2 3 1




Sample Output
2
1

3