Rabbit Olympics#3208
Organizing the Rabbit Olympics is a difficult task, even for such a dedicated rabbit as Stan. Stan tries to make the event spectacular, but also, being a patriot of his country, wants to make it easier for the audience to attend this grand event.
Stan knows that the key to success is simplification. He has simplified his country to one dimension, so that the location of each city in Rabbitland can be represented by a single integer. The positions of all cities are given. Stan can build no more than stadiums. He wants to build them so as to minimize the greatest distance (in one dimension, of course) that fans will need to travel to the nearest stadium. Help Stan calculate this value in advance.
The first line contains two space-separated integers: the number of cities (1 \leq N \leq 100\,000) and the number of stadiums (1 \leq K \leq 100\,000). The second line contains a list of city coordinates— space-separated integers, each of which by absolute value does not exceed 10^9.
Print the answer as a single number with exactly two digits after the decimal point.
Esempio 1