Maximum Non-overlapping Bridges

easy
1. You are given a number n, representing the number of bridges on a river.
2. You are given n pair of numbers, representing the north bank and south bank co-ordinates of each bridge.
3. You are required to print the count of maximum number of non-overlapping bridges.

Input Format

A number n .. n pair of number each on a separate line (and pair separated by space)

Output Format

A number representing the count of maximum number of non-overlapping bridges.

Constraints

0 <= n <= 20
0 <= n1n, n1s, n2n, n2s, .. <= 100

Notice

Try First, Check Solution later

1. You should first read the question and watch the question video.
2. Think of a solution approach, then try and submit the question on editor tab.
3. We strongly advise you to watch the solution video for prescribed approach.

Example

Input
10
10 20
2 7
8 15
17 3
21 40
50 4
41 57
60 80
80 90
1 30
Output
7
Previous
Minimum Cost To Make Two Strings Identical
Next
Longest Palindromic Subsequences

Related Questions