Background

This problem is a shortened version that keeps the original meaning unchanged.

Problem Description

FJ is attending events.

He wants to attend as many of the $N$ events as possible. After finishing one event, he can immediately attend the next one.

Given the list of events FJ can attend, their start time $T$ and duration $L$, find the maximum number of events FJ can attend.

FJ will not leave any event early.

Input Format

The first line contains an integer $N$.

Lines $2$ to $N+1$: each line contains two integers $T$ and $L$ separated by a space, with the meaning described above.

Output Format

Output only one line: the maximum number of events FJ can attend.

7
1 6
8 6
14 5
19 2
1 8
18 3
10 6

4

Hint

$1\le T,L\le 10^5$

$1\le N\le 10^4$

Translated by ChatGPT 5