gods/trees/binaryheap/binaryheap_test.go

501 lines
12 KiB
Go

// Copyright (c) 2015, Emir Pasic. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package binaryheap
import (
"math/rand"
"strings"
"testing"
)
func TestBinaryHeapPush(t *testing.T) {
heap := NewWithIntComparator()
if actualValue := heap.Empty(); actualValue != true {
t.Errorf("Got %v expected %v", actualValue, true)
}
heap.Push(3) // [3]
heap.Push(2) // [2,3]
heap.Push(1) // [1,3,2](2 swapped with 1, hence last)
if actualValue := heap.Values(); actualValue[0].(int) != 1 || actualValue[1].(int) != 3 || actualValue[2].(int) != 2 {
t.Errorf("Got %v expected %v", actualValue, "[1,2,3]")
}
if actualValue := heap.Empty(); actualValue != false {
t.Errorf("Got %v expected %v", actualValue, false)
}
if actualValue := heap.Size(); actualValue != 3 {
t.Errorf("Got %v expected %v", actualValue, 3)
}
if actualValue, ok := heap.Peek(); actualValue != 1 || !ok {
t.Errorf("Got %v expected %v", actualValue, 1)
}
}
func TestBinaryHeapPushBulk(t *testing.T) {
heap := NewWithIntComparator()
heap.Push(15, 20, 3, 1, 2)
if actualValue := heap.Values(); actualValue[0].(int) != 1 || actualValue[1].(int) != 2 || actualValue[2].(int) != 3 {
t.Errorf("Got %v expected %v", actualValue, "[1,2,3]")
}
if actualValue, ok := heap.Pop(); actualValue != 1 || !ok {
t.Errorf("Got %v expected %v", actualValue, 1)
}
}
func TestBinaryHeapPop(t *testing.T) {
heap := NewWithIntComparator()
if actualValue := heap.Empty(); actualValue != true {
t.Errorf("Got %v expected %v", actualValue, true)
}
heap.Push(3) // [3]
heap.Push(2) // [2,3]
heap.Push(1) // [1,3,2](2 swapped with 1, hence last)
heap.Pop() // [3,2]
if actualValue, ok := heap.Peek(); actualValue != 2 || !ok {
t.Errorf("Got %v expected %v", actualValue, 2)
}
if actualValue, ok := heap.Pop(); actualValue != 2 || !ok {
t.Errorf("Got %v expected %v", actualValue, 2)
}
if actualValue, ok := heap.Pop(); actualValue != 3 || !ok {
t.Errorf("Got %v expected %v", actualValue, 3)
}
if actualValue, ok := heap.Pop(); actualValue != nil || ok {
t.Errorf("Got %v expected %v", actualValue, nil)
}
if actualValue := heap.Empty(); actualValue != true {
t.Errorf("Got %v expected %v", actualValue, true)
}
if actualValue := heap.Values(); len(actualValue) != 0 {
t.Errorf("Got %v expected %v", actualValue, "[]")
}
}
func TestBinaryHeapRandom(t *testing.T) {
heap := NewWithIntComparator()
rand.Seed(3)
for i := 0; i < 10000; i++ {
r := int(rand.Int31n(30))
heap.Push(r)
}
prev, _ := heap.Pop()
for !heap.Empty() {
curr, _ := heap.Pop()
if prev.(int) > curr.(int) {
t.Errorf("Heap property invalidated. prev: %v current: %v", prev, curr)
}
prev = curr
}
}
func TestBinaryHeapIteratorOnEmpty(t *testing.T) {
heap := NewWithIntComparator()
it := heap.Iterator()
for it.Next() {
t.Errorf("Shouldn't iterate on empty heap")
}
}
func TestBinaryHeapIteratorNext(t *testing.T) {
heap := NewWithIntComparator()
heap.Push(3) // [3]
heap.Push(2) // [2,3]
heap.Push(1) // [1,3,2](2 swapped with 1, hence last)
it := heap.Iterator()
count := 0
for it.Next() {
count++
index := it.Index()
value := it.Value()
switch index {
case 0:
if actualValue, expectedValue := value, 1; actualValue != expectedValue {
t.Errorf("Got %v expected %v", actualValue, expectedValue)
}
case 1:
if actualValue, expectedValue := value, 3; actualValue != expectedValue {
t.Errorf("Got %v expected %v", actualValue, expectedValue)
}
case 2:
if actualValue, expectedValue := value, 2; actualValue != expectedValue {
t.Errorf("Got %v expected %v", actualValue, expectedValue)
}
default:
t.Errorf("Too many")
}
if actualValue, expectedValue := index, count-1; actualValue != expectedValue {
t.Errorf("Got %v expected %v", actualValue, expectedValue)
}
}
if actualValue, expectedValue := count, 3; actualValue != expectedValue {
t.Errorf("Got %v expected %v", actualValue, expectedValue)
}
}
func TestBinaryHeapIteratorPrev(t *testing.T) {
heap := NewWithIntComparator()
heap.Push(3) // [3]
heap.Push(2) // [2,3]
heap.Push(1) // [1,3,2](2 swapped with 1, hence last)
it := heap.Iterator()
for it.Next() {
}
count := 0
for it.Prev() {
count++
index := it.Index()
value := it.Value()
switch index {
case 0:
if actualValue, expectedValue := value, 1; actualValue != expectedValue {
t.Errorf("Got %v expected %v", actualValue, expectedValue)
}
case 1:
if actualValue, expectedValue := value, 3; actualValue != expectedValue {
t.Errorf("Got %v expected %v", actualValue, expectedValue)
}
case 2:
if actualValue, expectedValue := value, 2; actualValue != expectedValue {
t.Errorf("Got %v expected %v", actualValue, expectedValue)
}
default:
t.Errorf("Too many")
}
if actualValue, expectedValue := index, 3-count; actualValue != expectedValue {
t.Errorf("Got %v expected %v", actualValue, expectedValue)
}
}
if actualValue, expectedValue := count, 3; actualValue != expectedValue {
t.Errorf("Got %v expected %v", actualValue, expectedValue)
}
}
func TestBinaryHeapIteratorBegin(t *testing.T) {
heap := NewWithIntComparator()
it := heap.Iterator()
it.Begin()
heap.Push(2)
heap.Push(3)
heap.Push(1)
for it.Next() {
}
it.Begin()
it.Next()
if index, value := it.Index(), it.Value(); index != 0 || value != 1 {
t.Errorf("Got %v,%v expected %v,%v", index, value, 0, 1)
}
}
func TestBinaryHeapIteratorEnd(t *testing.T) {
heap := NewWithIntComparator()
it := heap.Iterator()
if index := it.Index(); index != -1 {
t.Errorf("Got %v expected %v", index, -1)
}
it.End()
if index := it.Index(); index != 0 {
t.Errorf("Got %v expected %v", index, 0)
}
heap.Push(3) // [3]
heap.Push(2) // [2,3]
heap.Push(1) // [1,3,2](2 swapped with 1, hence last)
it.End()
if index := it.Index(); index != heap.Size() {
t.Errorf("Got %v expected %v", index, heap.Size())
}
it.Prev()
if index, value := it.Index(), it.Value(); index != heap.Size()-1 || value != 2 {
t.Errorf("Got %v,%v expected %v,%v", index, value, heap.Size()-1, 2)
}
}
func TestBinaryHeapIteratorFirst(t *testing.T) {
heap := NewWithIntComparator()
it := heap.Iterator()
if actualValue, expectedValue := it.First(), false; actualValue != expectedValue {
t.Errorf("Got %v expected %v", actualValue, expectedValue)
}
heap.Push(3) // [3]
heap.Push(2) // [2,3]
heap.Push(1) // [1,3,2](2 swapped with 1, hence last)
if actualValue, expectedValue := it.First(), true; actualValue != expectedValue {
t.Errorf("Got %v expected %v", actualValue, expectedValue)
}
if index, value := it.Index(), it.Value(); index != 0 || value != 1 {
t.Errorf("Got %v,%v expected %v,%v", index, value, 0, 1)
}
}
func TestBinaryHeapIteratorLast(t *testing.T) {
tree := NewWithIntComparator()
it := tree.Iterator()
if actualValue, expectedValue := it.Last(), false; actualValue != expectedValue {
t.Errorf("Got %v expected %v", actualValue, expectedValue)
}
tree.Push(2)
tree.Push(3)
tree.Push(1) // [1,3,2](2 swapped with 1, hence last)
if actualValue, expectedValue := it.Last(), true; actualValue != expectedValue {
t.Errorf("Got %v expected %v", actualValue, expectedValue)
}
if index, value := it.Index(), it.Value(); index != 2 || value != 2 {
t.Errorf("Got %v,%v expected %v,%v", index, value, 2, 2)
}
}
func TestBinaryHeapIteratorNextTo(t *testing.T) {
// Sample seek function, i.e. string starting with "b"
seek := func(index int, value interface{}) bool {
return strings.HasSuffix(value.(string), "b")
}
// NextTo (empty)
{
tree := NewWithStringComparator()
it := tree.Iterator()
for it.NextTo(seek) {
t.Errorf("Shouldn't iterate on empty list")
}
}
// NextTo (not found)
{
tree := NewWithStringComparator()
tree.Push("xx")
tree.Push("yy")
it := tree.Iterator()
for it.NextTo(seek) {
t.Errorf("Shouldn't iterate on empty list")
}
}
// NextTo (found)
{
tree := NewWithStringComparator()
tree.Push("aa")
tree.Push("bb")
tree.Push("cc")
it := tree.Iterator()
it.Begin()
if !it.NextTo(seek) {
t.Errorf("Shouldn't iterate on empty list")
}
if index, value := it.Index(), it.Value(); index != 1 || value.(string) != "bb" {
t.Errorf("Got %v,%v expected %v,%v", index, value, 1, "bb")
}
if !it.Next() {
t.Errorf("Should go to first element")
}
if index, value := it.Index(), it.Value(); index != 2 || value.(string) != "cc" {
t.Errorf("Got %v,%v expected %v,%v", index, value, 2, "cc")
}
if it.Next() {
t.Errorf("Should not go past last element")
}
}
}
func TestBinaryHeapIteratorPrevTo(t *testing.T) {
// Sample seek function, i.e. string starting with "b"
seek := func(index int, value interface{}) bool {
return strings.HasSuffix(value.(string), "b")
}
// PrevTo (empty)
{
tree := NewWithStringComparator()
it := tree.Iterator()
it.End()
for it.PrevTo(seek) {
t.Errorf("Shouldn't iterate on empty list")
}
}
// PrevTo (not found)
{
tree := NewWithStringComparator()
tree.Push("xx")
tree.Push("yy")
it := tree.Iterator()
it.End()
for it.PrevTo(seek) {
t.Errorf("Shouldn't iterate on empty list")
}
}
// PrevTo (found)
{
tree := NewWithStringComparator()
tree.Push("aa")
tree.Push("bb")
tree.Push("cc")
it := tree.Iterator()
it.End()
if !it.PrevTo(seek) {
t.Errorf("Shouldn't iterate on empty list")
}
if index, value := it.Index(), it.Value(); index != 1 || value.(string) != "bb" {
t.Errorf("Got %v,%v expected %v,%v", index, value, 1, "bb")
}
if !it.Prev() {
t.Errorf("Should go to first element")
}
if index, value := it.Index(), it.Value(); index != 0 || value.(string) != "aa" {
t.Errorf("Got %v,%v expected %v,%v", index, value, 0, "aa")
}
if it.Prev() {
t.Errorf("Should not go before first element")
}
}
}
func TestBinaryHeapSerialization(t *testing.T) {
heap := NewWithStringComparator()
heap.Push("c") // ["c"]
heap.Push("b") // ["b","c"]
heap.Push("a") // ["a","c","b"]("b" swapped with "a", hence last)
var err error
assert := func() {
if actualValue := heap.Values(); actualValue[0].(string) != "a" || actualValue[1].(string) != "c" || actualValue[2].(string) != "b" {
t.Errorf("Got %v expected %v", actualValue, "[1,3,2]")
}
if actualValue := heap.Size(); actualValue != 3 {
t.Errorf("Got %v expected %v", actualValue, 3)
}
if actualValue, ok := heap.Peek(); actualValue != "a" || !ok {
t.Errorf("Got %v expected %v", actualValue, "a")
}
if err != nil {
t.Errorf("Got error %v", err)
}
}
assert()
json, err := heap.ToJSON()
assert()
err = heap.FromJSON(json)
assert()
}
func benchmarkPush(b *testing.B, heap *Heap, size int) {
for i := 0; i < b.N; i++ {
for n := 0; n < size; n++ {
heap.Push(n)
}
}
}
func benchmarkPop(b *testing.B, heap *Heap, size int) {
for i := 0; i < b.N; i++ {
for n := 0; n < size; n++ {
heap.Pop()
}
}
}
func BenchmarkBinaryHeapPop100(b *testing.B) {
b.StopTimer()
size := 100
heap := NewWithIntComparator()
for n := 0; n < size; n++ {
heap.Push(n)
}
b.StartTimer()
benchmarkPop(b, heap, size)
}
func BenchmarkBinaryHeapPop1000(b *testing.B) {
b.StopTimer()
size := 1000
heap := NewWithIntComparator()
for n := 0; n < size; n++ {
heap.Push(n)
}
b.StartTimer()
benchmarkPop(b, heap, size)
}
func BenchmarkBinaryHeapPop10000(b *testing.B) {
b.StopTimer()
size := 10000
heap := NewWithIntComparator()
for n := 0; n < size; n++ {
heap.Push(n)
}
b.StartTimer()
benchmarkPop(b, heap, size)
}
func BenchmarkBinaryHeapPop100000(b *testing.B) {
b.StopTimer()
size := 100000
heap := NewWithIntComparator()
for n := 0; n < size; n++ {
heap.Push(n)
}
b.StartTimer()
benchmarkPop(b, heap, size)
}
func BenchmarkBinaryHeapPush100(b *testing.B) {
b.StopTimer()
size := 100
heap := NewWithIntComparator()
b.StartTimer()
benchmarkPush(b, heap, size)
}
func BenchmarkBinaryHeapPush1000(b *testing.B) {
b.StopTimer()
size := 1000
heap := NewWithIntComparator()
for n := 0; n < size; n++ {
heap.Push(n)
}
b.StartTimer()
benchmarkPush(b, heap, size)
}
func BenchmarkBinaryHeapPush10000(b *testing.B) {
b.StopTimer()
size := 10000
heap := NewWithIntComparator()
for n := 0; n < size; n++ {
heap.Push(n)
}
b.StartTimer()
benchmarkPush(b, heap, size)
}
func BenchmarkBinaryHeapPush100000(b *testing.B) {
b.StopTimer()
size := 100000
heap := NewWithIntComparator()
for n := 0; n < size; n++ {
heap.Push(n)
}
b.StartTimer()
benchmarkPush(b, heap, size)
}