LIS2  Another Longest Increasing Subsequence Problem
Given a sequence of N pairs of integers, find the length of the longest increasing subsequence of it.
An increasing sequence A_{1}..A_{n} is a sequence such that for every i < j, A_{i} < A_{j}.
A subsequence of a sequence is a sequence that appears in the same relative order, but not necessarily contiguous.
A pair of integers (x_{1}, y_{1}) is less than (x_{2}, y_{2}) iff x_{1} < x_{2} and y_{1} < y_{2}.
Input
The first line of input contains an integer N (2 ≤ N ≤ 100000).
The following N lines consist of N pairs of integers (x_{i}, y_{i}) (10^{9} ≤ x_{i}, y_{i} ≤ 10^{9}).
Output
The output contains an integer: the length of the longest increasing subsequence of the given sequence.
Example
Input: 8 1 3 3 2 1 1 4 5 6 3 9 9 8 7 7 6 Output: 3
hide comments
theph0enix:
20160224 07:25:28
How do we compare (1, 3) and say (2, 3) since by the given definition of inequality these two pairs are neither less nor greater than the other. They cant even be considered equal since (1,3) is less than (2, 4) but (2, 4) is again neither less nor greater than (2, 3). 

abhishekrahul:
20151221 05:28:01
what it means TLE #3 ???


sherlocklives:
20151220 11:35:06
compilation error. compiling in system and ideone though :


Dhawal Harkawat:
20151106 06:54:37
AC..nlog^2n passes::D 

epsilon:
20151021 10:22:38
may someone plz tell me what it means:


Vivek:
20150723 13:29:06
nlogn solution : http://comscigate.com/Books/contests/icpc.pdf 

santamaria:
20150706 12:34:19
Check For This


Chandrakanth :
20150612 11:08:45
Wrong answer test #1. Isn't the first test case the one given in the example itself?If it is then my program gives the correct output 3. Last edit: 20150612 11:10:17 

anando_du:
20150304 19:50:41
_ are u kidding with me !!! wrong ans#1 ? 

mkrjn99:
20141203 15:08:52
Binary search continues to amaze me! 
Added by:  Bin Jin 
Date:  20080120 
Time limit:  0.345s 
Source limit:  50000B 
Memory limit:  1536MB 
Cluster:  Cube (Intel G860) 
Languages:  All except: C++ 5 