5.9 KiB
5.9 KiB
id | title | challengeType | forumTopicId |
---|---|---|---|
587d8254367417b2b2512c6f | Perform a Subset Check on Two Sets of Data | 1 | 301707 |
Description
Set
data structure called isSubsetOf
. This will compare the first set against the second, and if the first set is fully contained within the second, it will return true
.
For example, if setA = ['a','b']
and setB = ['a','b','c','d']
, then setA
is a subset of setB
, so setA.isSubsetOf(setB)
should return true
.
Instructions
Tests
tests:
- text: Your <code>Set</code> class should have a <code>isSubsetOf</code> method.
testString: assert((function(){var test = new Set(); return (typeof test.isSubsetOf === 'function')})());
- text: The first Set() should be contained in the second Set
testString: assert((function(){var setA = new Set(); var setB = new Set(); setA.add('a'); setB.add('b'); setB.add('c'); setB.add('a'); setB.add('d'); var aIsSubsetOfB = setA.isSubsetOf(setB);return (aIsSubsetOfB === true)})());
- text: <code>['a', 'b'].isSubsetOf(['a', 'b', 'c', 'd'])</code> should return <code>true</code>
testString: assert((function(){var setA = new Set(); var setB = new Set(); setA.add('a'); setA.add('b'); setB.add('a'); setB.add('b'); setB.add('c'); setB.add('d'); var aIsSubsetOfB = setA.isSubsetOf(setB); return (aIsSubsetOfB === true)})());
- text: <code>['a', 'b', 'c'].isSubsetOf(['a', 'b'])</code> should return <code>false</code>
testString: assert((function(){var setA = new Set(); var setB = new Set(); setA.add('a'); setA.add('b'); setA.add('c'); setB.add('a'); setB.add('b'); var aIsSubsetOfB = setA.isSubsetOf(setB); return (aIsSubsetOfB === false)})());
- text: <code>[].isSubsetOf([])</code> should return <code>true</code>
testString: assert((function(){var setA = new Set(); var setB = new Set(); var aIsSubsetOfB = setA.isSubsetOf(setB); return (aIsSubsetOfB === true)})());
- text: <code>['a', 'b'].isSubsetOf(['c', 'd'])</code> should return <code>false</code>
testString: assert((function(){var setA = new Set(); var setB = new Set(); setA.add('a'); setA.add('b'); setB.add('c'); setB.add('d'); var aIsSubsetOfB = setA.isSubsetOf(setB); return (aIsSubsetOfB === false)})());
Challenge Seed
class Set {
constructor() {
// This will hold the set
this.dictionary = {};
this.length = 0;
}
// This method will check for the presence of an element and return true or false
has(element) {
return this.dictionary[element] !== undefined;
}
// This method will return all the values in the set
values() {
return Object.keys(this.dictionary);
}
// This method will add an element to the set
add(element) {
if (!this.has(element)) {
this.dictionary[element] = true;
this.length++;
return true;
}
return false;
}
// This method will remove an element from a set
remove(element) {
if (this.has(element)) {
delete this.dictionary[element];
this.length--;
return true;
}
return false;
}
// This method will return the size of the set
size() {
return this.length;
}
// This is our union method
union(set) {
const newSet = new Set();
this.values().forEach(value => {
newSet.add(value);
})
set.values().forEach(value => {
newSet.add(value);
})
return newSet;
}
// This is our intersection method
intersection(set) {
const newSet = new Set();
let largeSet;
let smallSet;
if (this.dictionary.length > set.length) {
largeSet = this;
smallSet = set;
} else {
largeSet = set;
smallSet = this;
}
smallSet.values().forEach(value => {
if (largeSet.dictionary[value]) {
newSet.add(value);
}
})
return newSet;
}
difference(set) {
const newSet = new Set();
this.values().forEach(value => {
if (!set.dictionary[value]) {
newSet.add(value);
}
})
return newSet;
}
// Only change code below this line
// Only change code above this line
}
Solution
class Set {
constructor() {
this.dictionary = {};
this.length = 0;
}
has(element) {
return this.dictionary[element] !== undefined;
}
values() {
return Object.keys(this.dictionary);
}
add(element) {
if (!this.has(element)) {
this.dictionary[element] = true;
this.length++;
return true;
}
return false;
}
remove(element) {
if (this.has(element)) {
delete this.dictionary[element];
this.length--;
return true;
}
return false;
}
size() {
return this.length;
}
union(set) {
const newSet = new Set();
this.values().forEach(value => {
newSet.add(value);
})
set.values().forEach(value => {
newSet.add(value);
})
return newSet;
}
intersection(set) {
const newSet = new Set();
let largeSet;
let smallSet;
if (this.dictionary.length > set.length) {
largeSet = this;
smallSet = set;
} else {
largeSet = set;
smallSet = this;
}
smallSet.values().forEach(value => {
if (largeSet.dictionary[value]) {
newSet.add(value);
}
})
return newSet;
}
difference(set) {
const newSet = new Set();
this.values().forEach(value => {
if (!set.dictionary[value]) {
newSet.add(value);
}
})
return newSet;
}
isSubsetOf(set) {
for(const value of this.values()){
if(!set.dictionary[value]) return false;
}
return true
}
}