RosettaCodeData/Task/Priority-queue/Ruby/priority-queue.rb

52 lines
759 B
Ruby

class PriorityQueueNaive
def initialize
@q = Hash.new { |h, k| h[k] = []}
@priorities = []
end
def push(priority, item)
@q[priority] << item
@priorities = @q.keys.sort
end
def pop
p = @priorities[0]
item = @q[p].shift
if @q[p].empty?
@q.delete(p)
@priorities.shift
end
item
end
def peek
if not empty?
@q[@priorities[0]][0]
end
end
def empty?
@priorities.empty?
end
def inspect
@q.inspect
end
end
test = [
[6, "drink tea"],
[3, "Clear drains"],
[4, "Feed cat"],
[5, "Make tea"],
[6, "eat biscuit"],
[1, "Solve RC tasks"],
[2, "Tax return"],
]
pq = PriorityQueueNaive.new
test.each {|pr, str| pq.push(pr, str) }
until pq.empty?
puts pq.pop
end