ABC174

https://atcoder.jp/contests/abc174
過去問。
　

A: Air Conditioner

x = gets.to_i
puts (x >= 30) ? "Yes" : "No"

B: Distance

n, d = gets.split.map(&:to_i)
coordinates = n.times.map {gets.split.map(&:to_i)}

puts coordinates.count {|x, y| x * x + y * y <= d * d}