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Heap = require '..'
{random} = Math
describe 'Heap#push, Heap#pop', ->
it 'should sort an array using push and pop', ->
heap = new Heap
heap.push(random()) for i in [1..10]
sorted = (heap.pop() until heap.empty())
sorted.slice().sort().should.eql(sorted)
it 'should work with custom comparison function', ->
cmp = (a, b) ->
return -1 if a > b
return 1 if a < b
0
heap = new Heap(cmp)
heap.push(random()) for i in [1..10]
sorted = (heap.pop() until heap.empty())
sorted.slice().sort().reverse().should.eql(sorted)
describe 'Heap#replace', ->
it 'should behave like pop() followed by push()', ->
heap = new Heap
heap.push(v) for v in [1..5]
heap.replace(3).should.eql(1)
heap.toArray().sort().should.eql([2,3,3,4,5])
describe 'Heap#pushpop', ->
it 'should behave like push() followed by pop()', ->
heap = new Heap
heap.push(v) for v in [1..5]
heap.pushpop(6).should.eql(1)
heap.toArray().sort().should.eql([2..6])
describe 'Heap#contains', ->
it 'should return whether it contains the value', ->
heap = new Heap
heap.push(v) for v in [1..5]
heap.contains(v).should.be.true for v in [1..5]
heap.contains(0).should.be.false
heap.contains(6).should.be.false
describe 'Heap#peek', ->
it 'should return the top value', ->
heap = new Heap
heap.push(1)
heap.peek().should.eql(1)
heap.push(2)
heap.peek().should.eql(1)
heap.pop()
heap.peek().should.eql(2)
describe 'Heap#clone', ->
it 'should return a cloned heap', ->
a = new Heap
a.push(v) for v in [1..5]
b = a.clone()
a.toArray().should.eql(b.toArray())
describe 'Heap.nsmallest', ->
it 'should return exactly n elements when size() >= n', ->
Heap.nsmallest([1..10], 3).should.eql([1..3])
array = [1,3,2,1,3,4,4,2,3,4,5,1,2,3,4,5,2,1,3,4,5,6,7,2]
Heap.nsmallest(array, 2).should.eql([1, 1])
it 'should return size() elements when size() <= n', ->
Heap.nsmallest([3..1], 10).should.eql([1..3])
describe 'Heap.nlargest', ->
it 'should return exactly n elements when size() >= n', ->
Heap.nlargest([1..10], 3).should.eql([10..8])
it 'should return size() elements when size() <= n', ->
Heap.nlargest([3..1], 10).should.eql([3..1])
describe 'Heap#updateItem', ->
it 'should return correct order', ->
a = x: 1
b = x: 2
c = x: 3
h = new Heap (m, n) -> m.x - n.x
h.push(a)
h.push(b)
h.push(c)
c.x = 0
h.updateItem(c)
h.pop().should.eql(c)
it 'should return correct order when used statically', ->
a = x: 1
b = x: 2
c = x: 3
h = []
cmp = (m, n) -> m.x - n.x
Heap.push(h, a, cmp)
Heap.push(h, b, cmp)
Heap.push(h, c, cmp)
c.x = 0
Heap.updateItem(h, c, cmp)
Heap.pop(h, cmp).should.eql(c)