The Focus Window

You have N tasks, each with a range $[S_i, E_i]$. You want to set a 'focus window' of fixed duration W. A task is 'contained' if its entire duration $[S_i, E_i]$ falls within the focus window $[T, T+W]$ for some start time T. Find the maximum number of tasks you can contain in a single window of duration W. Input Format: - Two integers: W (window size) and N (number of tasks). - N lines, each containing S and E. Output Format: - A single integer representing the maximum tasks contained. Example: Input: 10 3 5 12 15 22 8 18 Output: 2 Explanation: For W=10, a window from T=8 to T=18 contains [8, 18]. A window from T=5 to T=15 contains [5, 12]. A window from T=12 to T=22 contains [15, 22]. No window contains all three because the span from the start of the earliest to the end of the latest is too large.