The Consensus Window

N researchers are observing a rare celestial event. Each researcher 'i' provides a time window [start_i, end_i] during which their equipment is calibrated and active. Scientists need to find the specific window where ALL researchers are active simultaneously. If no such window exists, output NONE. Input Format: The first line contains N. The next N lines contain start and end times. Output Format: Two integers 'start end' of the intersection, or NONE. Example: Input: 3 10 50 20 60 30 45 Output: 30 45