Radars#616
There are cities located on a straight line. A broadcasting company wants to install radars in three of these cities to maximize the system's power. If the radars are placed in cities with coordinates x_1, x_2, and x_3, the power is (x_3 - x_2) \cdot (x_2 - x_1), i.e., the product of the distances between the cities. Find the largest possible broadcasting power.
The input contains the integer (3 \le n \le 100\,000) — the number of cities, followed by integers, each not exceeding in absolute value, representing the coordinates of the cities.
Print the maximum possible broadcasting power.
Example 1