AtCoder Regular Contest #004

http://arc004.contest.atcoder.jp/

A, B問題だけ。 それ以降はわかりませんでした。(馬鹿

A - 2点間距離の最大値 ( The longest distance )

n = gets.chomp.to_i
 
points = []
n.times do
  points << gets.chomp.split( " " ).map{ |e| e.to_i }
end
 
max = 0.0
points.combination( 2 ) { |a, b| 
  d = Math.sqrt( (a[0] - b[0]) ** 2 + (a[1] - b[1]) ** 2 )
  max = [max, d].max
}
 
puts max

B - 2点間距離の最大と最小 ( Maximum and Minimum )

n = gets.chomp.to_i
 
points = []
n.times do
  points << gets.chomp.to_i
end
sum = points.inject(0) { |sum, i| sum + i }
max = points.max
puts sum
puts [0, 2 * max - sum].max