45 lines
1004 B
Crystal
45 lines
1004 B
Crystal
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require "./spec_helper"
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describe Array do
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describe "#heapify" do
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it "preserves the elements in the array" do
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a = Array(Int32).new(20) { rand(10) }
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a.sort.should eq(a.clone.heapify!.sort)
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end
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it "creates an array with proper ordering" do
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a = Array(Int32).new(20) { rand(10) }
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a.heapify!
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a.is_heap?.should be_true
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end
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it "maintains heap property while popping" do
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a = Array(Int32).new(20) { rand(10) }
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a.heapify!
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20.times do |i|
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a.heap_pop
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a.is_heap?.should be_true
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end
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end
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it "maintains heap property while pushing" do
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a = [] of Int32
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20.times do
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a.heap_push(rand 10)
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a.is_heap?.should be_true
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end
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end
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it "pops numbers in descending order" do
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a = Array(Int32).new(20) { rand(10) }
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a.heapify!
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last = Int32::MAX
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20.times do
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popped = a.heap_pop
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popped.should be <= last
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last = popped
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end
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end
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end
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end
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