Noor and his pond
Tag(s):

## Algorithms, Medium, Quick Sort, Quicksort, Quicksort, Quicksort, Sorting

Problem
Editorial
Analytics

Statement

Noor is going fish farming. There are N types of fish. Each type of fish has size(S) and eating factor(E). A fish with eating factor of E, will eat all the fish of size $\le E$.

Help Noor to select a set of fish such that the size of the set is maximized as well as they do not eat each other.

Constraints

$1 \le T \le 3$

$1 \le N \le 100000$

$1 \le S_i , E_i \le 10^9$

$S_i > E_i$

Input

The first line contains T, the number of test cases. The first line of a test case contains an integers N. N is the number of types of fish. Each of the next N lines contains two integers S and E meaning the size and eating factor of a fish.

Output

For each test cases, print a single integer, the maximum number of fish Noor can have in his pond.

SAMPLE INPUT
1
3
4 1
5 4
7 3

SAMPLE OUTPUT
2
Explanation

In the sample input, Noor can select the first and the third fish.

Time Limit: 1.0 sec(s) for each input file.
Memory Limit: 256 MB
Source Limit: 1024 KB
Marking Scheme: Marks are awarded when all the testcases pass.
Allowed Languages: Bash, C, C++, C++14, Clojure, C#, D, Erlang, F#, Go, Groovy, Haskell, Java, Java 8, JavaScript(Rhino), JavaScript(Node.js), Julia, Kotlin, Lisp, Lisp (SBCL), Lua, Objective-C, OCaml, Octave, Pascal, Perl, PHP, Python, Python 3, R(RScript), Racket, Ruby, Rust, Scala, Swift, Swift-4.1, TypeScript, Visual Basic

## CODE EDITOR

Initializing Code Editor...

## This Problem was Asked in Challenge Name

August Circuits '18

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