Deep Space Silence

An interstellar radio array receives signals in specific time windows. You are given a list of time intervals [start, end] where signals were detected. Your task is to find the duration of the longest continuous period of 'silence' (no signals detected) between the first recorded signal's start time and the last recorded signal's end time. Input Format: The first line contains an integer N, the number of signal intervals. The next N lines each contain two integers, 'start' and 'end', representing a signal window. Output Format: Print a single integer representing the length of the longest silent gap. Example: Input: 3 10 20 50 60 25 35 Output: 15 (Gaps are [20, 25] length 5 and [35, 50] length 15. Longest is 15.)