summaryrefslogtreecommitdiffstats
path: root/Scala/funsets/src/main/scala
diff options
context:
space:
mode:
Diffstat (limited to 'Scala/funsets/src/main/scala')
-rw-r--r--Scala/funsets/src/main/scala/funsets/FunSets.scala22
1 files changed, 12 insertions, 10 deletions
diff --git a/Scala/funsets/src/main/scala/funsets/FunSets.scala b/Scala/funsets/src/main/scala/funsets/FunSets.scala
index 15a6bfc..99b0748 100644
--- a/Scala/funsets/src/main/scala/funsets/FunSets.scala
+++ b/Scala/funsets/src/main/scala/funsets/FunSets.scala
@@ -20,25 +20,25 @@ object FunSets {
/**
* Returns the set of the one given element.
*/
- def singletonSet(elem: Int): Set = (x => x == elem)
+ def singletonSet(elem: Int): Set = x => x == elem
/**
* Returns the union of the two given sets,
* the sets of all elements that are in either `s` or `t`.
*/
- def union(s: Set, t: Set): Set = (x => s(x) | t(x))
+ def union(s: Set, t: Set): Set = x => s(x) | t(x)
/**
* Returns the intersection of the two given sets,
* the set of all elements that are both in `s` and `t`.
*/
- def intersect(s: Set, t: Set): Set = (x => s(x) & t(x))
+ def intersect(s: Set, t: Set): Set = x => s(x) & t(x)
/**
* Returns the difference of the two given sets,
* the set of all elements of `s` that are not in `t`.
*/
- def diff(s: Set, t: Set): Set = (x => s(x) & !t(x))
+ def diff(s: Set, t: Set): Set = x => s(x) & !t(x)
/**
* Returns the subset of `s` for which `p` holds.
@@ -56,23 +56,25 @@ object FunSets {
*/
def forall(s: Set, p: Int => Boolean): Boolean = {
def iter(a: Int): Boolean = {
- if (???) ???
- else if (???) ???
- else iter(???)
+ if (a > bound) true
+ else if (contains(s, a) && !p(a)) false
+ else iter(a + 1)
}
- iter(???)
+ iter(-bound)
}
/**
* Returns whether there exists a bounded integer within `s`
* that satisfies `p`.
*/
- def exists(s: Set, p: Int => Boolean): Boolean = ???
+ // elements of s do NOT all NOT satisfy p
+ def exists(s: Set, p: Int => Boolean): Boolean = !forall(s, x => !p(x))
/**
* Returns a set transformed by applying `f` to each element of `s`.
*/
- def map(s: Set, f: Int => Int): Set = ???
+ // x is in S' if exists y in S so that f(y) = x
+ def map(s: Set, f: Int => Int): Set = x => exists(s, y => f(y) == x)
/**
* Displays the contents of a set