区間スケジューリング問題

shceduling.rb

## 区間スケジューリング問題
## http://rubyfiddle.com/riddles/da7c6

n = 5
s = [1, 2, 4, 6, 8]
t = [3, 5, 7, 9, 10]
a = []

ans = 0
last = 0

n.times{|i|
  a[i] = [t[i],s[i]]
  }

a.sort!

n.times{|i|
  if last < a[i][1]
    ans += 1
    last = a[i][0]
  end
  }

puts ans