azalea/kotlin-fork
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

Added sequences that helped solve Project Euler problems

Browse Source
This commit is contained in:
Franck Rasolo
2012-03-21 10:27:17 +00:00
parent fe17d83493
commit ef89a38de1
3 changed files with 97 additions and 29 deletions
Download Patch File Download Diff File Expand all files Collapse all files
libraries/stdlib/src/sequences/Sequences.kt
+5 -5
View File
@@ -13,17 +13,17 @@ private fun <T> asSequence(iterator: Iterator<T>) = Sequence<T> { if (iterator.h
private fun <T> asSequence(iterator: java.util.Iterator<T>) = Sequence<T> { if (iterator.hasNext()) iterator.next() else null }
/**
* Produces the [cartesian square](http://en.wikipedia.org/wiki/Cartesian_product#Cartesian_square_and_Cartesian_power)
* as sequence of order pairs of elements lazily obtained from this range of elements
* Produces the [cartesian product](http://en.wikipedia.org/wiki/Cartesian_product#n-ary_product) as a sequence of ordered pairs of elements lazily obtained
* from two [[Iterable]] instances
*/
fun <T> Iterable<T>.cartesianSquare(): Sequence<#(T, T)> {
val first = iterator(); var second = iterator(); var a: T? = null
fun <T> Iterable<T>.times(other: Iterable<T>): Sequence<#(T, T)> {
val first = iterator(); var second = other.iterator(); var a: T? = null
fun nextPair(): #(T, T)? {
if (a == null && first.hasNext) a = first.next()
if (second.hasNext) return #(a.sure(), second.next())
if (first.hasNext) {
a = first.next(); second = iterator()
a = first.next(); second = other.iterator()
return #(a.sure(), second.next())
}
return null