Course Schedule III

Problem Statement

Course Schedule III Problem Description There are `n` different online courses numbered from 1 to `n`. You are given an array `courses` where `courses[i] = [duration_i, lastDay_i]` indicate that the `i^{th}` course should be taken continuously for `duration_i` days and must be finished before or on `lastDay_i`. You will start on the `1^{st}` day and you cannot take two or more courses simultaneously. Return the maximum number of courses that you can take. Examples Example 1: Input: courses = [[100,200],[200,1300],[1000,1250],[2000,3200]] Output: 3 Explanation: There are totally 4 courses, but you can take 3 courses at most: First, take the `1^{st}` course, it costs 100 days so you will finish it on the `100^{th}` day, and ready to take the next course on the `101^{st}` day. Second, take the `3^{rd}` course, it costs 1000 days so you will finish it on the `1100^{th}` day, and ready to take the next course on the `1101^{st}` day. Third, take the `2^{nd}` course, it costs 200 days so you