-
Notifications
You must be signed in to change notification settings - Fork 0
/
utils.kt
335 lines (282 loc) · 8.7 KB
/
utils.kt
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
package utils
import java.io.File
import java.io.IOException
import java.net.URI
import java.net.http.HttpClient
import java.net.http.HttpRequest
import java.net.http.HttpResponse
import java.time.Duration
import java.util.Arrays
object Utils
fun readFile(name: String): String {
val stream = Utils.javaClass.getResourceAsStream("/$name.txt")
require (stream != null) {
"No input @ /$name.txt!"
}
return stream.use { it.readBytes().toString(Charsets.UTF_8) }
}
fun readInput(year: Int, day: Int): String {
val file = File("").resolve(year.toString()).resolve("src").resolve("main").resolve("resources").resolve("day${day}.txt")
if (!file.exists()) {
val cookie = readFile("cookie").trim()
val ua = readFile("user-agent").trim()
val client = HttpClient.newBuilder()
.version(HttpClient.Version.HTTP_1_1)
.followRedirects(HttpClient.Redirect.NORMAL)
.connectTimeout(Duration.ofSeconds(5))
.build()
val request = HttpRequest.newBuilder()
.GET()
.uri(URI("https://adventofcode.com/${year}/day/${day}/input"))
.header("Cookie", cookie)
.header("User-Agent", ua)
.build()
val resp = client.send(request, HttpResponse.BodyHandlers.ofInputStream())
if (resp.statusCode() >= 400) {
throw IOException("Request to AoC servers failed, status=${resp.statusCode()}")
}
resp.body().use { input ->
file.outputStream().use { output ->
input.copyTo(output, bufferSize = 8192)
}
}
}
require (file.exists()) {
"Could not fetch input for $year / day $day"
}
return file.readText(Charsets.UTF_8)
}
fun <A, B> Pair<A, A>.map(fn: (A) -> B): Pair<B, B> = fn(first) to fn(second)
/**
* Merge a list of pairs into a map. If items are present with the same key multiple times then they will be
* reduced according to the collision function.
*
* Normal `mapOf`: `mapOf("a" to 1, "a" to 4, "b" to 2) == mapOf("a" to 4, "b" to 2)`
* `mergeToMap`: `listOf("a" to 1, "a" to 4, "b" to 2).mergeToMap { _, v1, v2 -> v1 + v2 } == mapOf("a" to 5, "b" to 2)`
*
*/
fun <K, V> List<Pair<K, V>>.mergeToMap(collisionFn: (K, V, V) -> V): Map<K, V> {
return groupBy(keySelector = Pair<K, V>::first, valueTransform = Pair<K, V>::second)
.mapValues { (k, v) -> v.reduce { v1, v2 -> collisionFn(k, v1, v2) } }
.toMap()
}
fun <T> Iterable<T>.withCounts(): Map<T, Int> {
return groupBy { it }.mapValues { (_, c) -> c.size }
}
fun <T> Iterable<T>.withLCounts(): Map<T, Long> {
return groupBy { it }.mapValues { (_, c) -> c.size.toLong() }
}
operator fun <T> List<T>.times(other: List<T>): List<Pair<T, T>> {
return flatMap { first ->
other.map { second ->
first to second
}
}
}
val <T> List<T>.permutations: Sequence<List<T>> get() {
val indices = IntArray(size) { it }
val list = MutableList(size) { this[it] }
return generateSequence(list as List<T>) { _ ->
val f = (size - 2 downTo 0).firstOrNull { indices[it] < indices[it + 1] } ?: return@generateSequence null
val n = (f + 1 until size).filter { indices[it] > indices[f] }.minBy { indices[it] }
indices[f] = indices[n].also {
indices[n] = indices[f]
}
Arrays.sort(indices, f + 1, size)
list.clear()
indices.mapTo(list) { this[it] }
list
}
}
val <T> List<T>.combinations: Sequence<List<T>> get() {
val list = MutableList(size) { this[it] }
val take = BooleanArray(size) { false }
return generateSequence(emptyList()) { _ ->
val lastFalse = take.lastIndexOf(false)
if (lastFalse == -1) {
return@generateSequence null
}
// flip lastFalse to true, following items to false
take[lastFalse] = true
(lastFalse + 1 until take.size).forEach {
take[it] = false
}
list.clear()
(0 .. lastFalse).forEach { i ->
if (take[i]) {
list.add(this[i])
}
}
return@generateSequence list
}
}
fun <T> List<T>.selections(count: Int): Sequence<List<T>> {
require (count <= size) {
"Cannot take $count items from a list of size $size"
}
val list = MutableList(size) { this[it] }
val take = BooleanArray(size) { it >= size - count }
return generateSequence(subList(size - count, size)) {
// find the last 1
val last = take.lastIndexOf(true)
// find the first preceding 0
val swap = take.asList().subList(0, last).lastIndexOf(false)
if (swap == -1) {
return@generateSequence null
}
// shift remaining items to the end of the list
val shiftCount = last - swap - 1
(size - shiftCount until size).forEach {
take[it] = true
}
(swap + 2 until size - shiftCount).forEach {
take[it] = false
}
take[swap] = true
take[swap + 1] = false
list.clear()
take.forEachIndexed { i, b ->
if (b) {
list.add(this[i])
}
}
return@generateSequence list
}
}
val <T> List<T>.pairs: Sequence<Pair<T, T>> get() {
return selections(2).map { (a, b) -> a to b }
}
fun <T> List<T>.product(other: List<T>): List<Pair<T, T>> = this * other
inline fun <T, V> List<T>.product(other: List<T>, fn: (v1: T, v2: T) -> V): List<V> {
return flatMap { first ->
other.map { second ->
fn(first, second)
}
}
}
inline fun <T, V> List<T>.productIndexed(other: List<T>, fn: (i1: Int, v1: T, i2: Int, v2: T) -> V): List<V> {
return flatMapIndexed { i1, v1 ->
other.mapIndexed { i2, v2 ->
fn(i1, v1, i2, v2)
}
}
}
fun <T> List<T>.product(): List<Pair<T, T>> {
return flatMapIndexed { index, first ->
subList(index + 1, size).map { second ->
first to second
}
}
}
inline fun <T, V> List<T>.product(fn: (v1: T, v2: T) -> V): List<V> {
return flatMapIndexed { index, first ->
subList(index + 1, size).map { second ->
fn(first, second)
}
}
}
inline fun <T, V> List<T>.productIndexed(fn: (i1: Int, v1: T, i2: Int, v2: T) -> V): List<V> {
return flatMapIndexed { i1, v1 ->
subList(i1 + 1, size).mapIndexed { i2, v2 ->
fn(i1, v1, i1 + 1 + i2, v2)
}
}
}
fun <T> Collection<T>.startsWith(other: Collection<T>): Boolean {
if (this.size < other.size) {
return false
}
val me = iterator()
val them = other.iterator()
while (them.hasNext()) {
if (me.next() != them.next()) {
return false
}
}
return true
}
inline fun <reified T> Iterable<T>.takeWhileInclusive(predicate: (T) -> Boolean): List<T> {
val list = ArrayList<T>()
for (item in this) {
list.add(item)
if (!predicate(item))
break
}
return list
}
val String.parts: List<String> get() = split(" ").mapNotNull { it.trim().takeIf(String::isNotEmpty) }
fun String.split(): Pair<String, String> {
val mid = length / 2
if (mid * 2 != length) {
badInput()
}
return substring(0, mid) to substring(mid)
}
fun String.findAll(needle: String): List<Int> {
val out = mutableListOf<Int>()
var index = indexOf(needle, 0)
while (index < this.length && index != -1) {
out += index
index = indexOf(needle, index + needle.length)
}
return out
}
fun <T> Collection<T>.split(): Pair<Collection<T>, Collection<T>> {
val halfSize = size / 2
if (halfSize * 2 != size) { badInput() }
return take(halfSize) to drop(halfSize)
}
val <T1, T2> Pair<T1, T2>.flipped: Pair<T2, T1> get() = second to first
inline fun pow2(n: Int): Int = 1 shl n
fun Int.pow(n: Int): Int {
var value = 1
require (n >= 0) {
"Cannot do int pow with negative exponent"
}
repeat(n) {
value *= this
}
return value
}
fun Long.pow(n: Int): Long {
var value = 1L
require (n >= 0) {
"Cannot do long pow with negative exponent"
}
repeat(n) {
value *= this
}
return value
}
fun Int.wrap(max: Int): Int {
return if (this > 0) {
this % max
} else {
(max + (this % max)) % max
}
}
/**
* Split the range into a triplet of ranges:
* - intersection of the two ranges
* - list of ranges in the first range but not the second
*/
infix fun LongRange.tesselateWith(other: LongRange): Pair<LongRange?, List<LongRange>> {
val intersection = (maxOf(first, other.first) .. minOf(last, other.last))
val left = (first .. minOf(last, other.first - 1))
val right = (maxOf(first, other.last + 1) .. last)
return intersection.takeIf { !it.isEmpty() } to listOf(left, right).filter { !it.isEmpty() }
}
/**
* Split the range into a triplet of ranges:
* - intersection of the two ranges
* - list of ranges in the first range but not the second
*/
infix fun IntRange.tesselateWith(other: IntRange): Pair<IntRange?, List<IntRange>> {
val intersection = (maxOf(first, other.first) .. minOf(last, other.last))
val left = (first .. minOf(last, other.first - 1))
val right = (maxOf(first, other.last + 1) .. last)
return intersection.takeIf { !it.isEmpty() } to listOf(left, right).filter { !it.isEmpty() }
}
fun badInput(): Nothing {
throw IllegalArgumentException("bad input")
}