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@Catharz
Created April 16, 2013 01:10
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Codility Omega 2013 - Falling Disks
def falling_disks(rings, disks)
min, disk = rings[0], 0
rings.each_index do |ring|
min = rings[ring] if rings[ring] < min
rings[ring] = min if rings[ring] > min
end
(rings.size - 1).downto(0) do |ring|
disk += 1 if disks[disk] <= rings[ring]
return disk if disk == disks.size
end
disk
end
require 'spec_helper'
require_relative '../falling_disks'
describe '#falling_disks' do
it 'passes the sanity check' do
rings, disks = [5, 6, 4, 3, 6, 2, 3], [2, 3, 5, 2, 4]
falling_disks(rings,disks).should == 4
end
it 'drops disks to the bottom' do
rings, disks = [5, 5, 5], [4, 4, 4]
falling_disks(rings,disks).should == 3
end
it 'only drops the number of rings that can fit' do
rings, disks = [5, 5, 5], [4, 4, 4, 4]
falling_disks(rings,disks).should == 3
end
it 'only drops disks that can fit' do
rings, disks = [5, 3, 5], [4, 4, 4, 4]
falling_disks(rings,disks).should == 1
end
it 'only drops as many disks as exist' do
rings, disks = [5, 5, 5, 5], [4, 4, 4]
falling_disks(rings,disks).should == 3
end
it 'only drops the first ring when only the first will fit' do
rings, disks = [7, 6, 6, 6, 19, 7, 7, 6, 8, 13, 9, 12], [7, 3, 2, 5, 6]
falling_disks(rings,disks).should == 1
end
it 'will not drop any disks when none will fit' do
rings, disks = [6, 15, 5, 17, 5, 20, 16, 17, 10, 13, 8, 10], [7, 4, 4, 3, 1]
falling_disks(rings,disks).should == 0
end
end
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