The Corporate Median Vibe

In a company tree, every employee has a 'base vibe' score. A manager's 'final vibe' is calculated as the median of their own base vibe and the final vibes of all their direct reports. If there's an even number of values, the median is the average of the middle two. Calculate the final vibe of the CEO (root node 0). Use floating point for all vibes. Input Format: Line 1: N (number of employees) Line 2: N floats (base vibes of employees 0 to N-1) Next N-1 lines: u v (manager u, report v) Example: Input: 3 10.0 20.0 30.0 0 1 0 2 Output: 20.0000