#include "set.h"

class Set<ValueType>

This class stores a collection of distinct elements.

The set uses a binary search tree (BST) structure internally. Because of this choice of internal representation, the ValueType for the type of elements stored in a Set must define a natural ordering through a less function and/or < operator so that the elements can be compared and ordered. The range-based for loop will iterate over the elements in sorted order. The Set operations to add/find/remove an element run in O(logN) time.
Constructor
Set()  O(1) Initializes a new set of the specified element type.
Methods
add(value)  O(log N) Adds an element to this set, if it was not already there.
clear()  O(N) Removes all elements from this set.
contains(value)  O(log N) Returns true if the specified value is in this set.
difference(otherSet)  O(Nlog N) Subtracts otherSet from this set. The difference removes those elements that appear in otherSet.
equals(set)  O(N) Returns true if the two sets contain the same elements.
first()  O(log N) Returns the first value in this set when considered in sorted order.
intersect(otherSet)  O(N log N) Intersects otherSet with this set. The intersection retains only those elements also contained in otherSet.
isEmpty()  O(1) Returns true if this set contains no elements.
isSubsetOf(otherSet)  O(N) Returns true if this set is a subset of otherSet.
isSupersetOf(otherSet)  O(N) Returns true if this set is a superset of otherSet.
last()  O(log N) Returns the last value in this set when considered in sorted order.
mapAll(fn)  O(N) Calls fn(value) for each element of this set.
remove(value)  O(log N) Removes an element from this set.
size()  O(1) Returns the number of elements in this set.
toString()  O(N) Returns a printable string representation of this set.
unionWith(otherSet)  O(N log N) Unions otherSet with this set. The union adds all elements from otherSet.
Operators
for (ValueType elem : set)  O(N) Iterates through the elements in a set.
set1 == set2  O(N) Evaluates to true if set1 and set2 contain the same elements.
set1 != set2  O(N) Evaluates to true if set1 and set2 are different.
set1 + set2  O(N) Creates a new set which is the union of set1 with set2.
set + value  O(N log N) Creates a new set which is the union of set with the single value.
set1 += set2  O(N log N) Adds all of the elements from set2 to set1.
set += value  O(log N) Adds the single value to set.
set1 - set2  O(N log N) Creates a new set containing the elements in set1 that aren't in set2.
set - value  O(log N) Creates a new set which contains all values in set minus value.
set1 -= set2  O(N log N) Removes the elements of set2 from set1.
set -= value  O(log N) Removes the single value from set.
set1 * set2  O(N log N) Creates a new set which is the intersection of set1 and set2.
set1 *= set2  O(N log N) Removes any elements from set1 that are not present in set2.
ostream << set  O(N) Outputs the contents of set to the given output stream.
istream >> set  O(N log N) Reads the contents of the given input stream into set.

Constructor detail


Set();
Creates an empty set of the specified element type. You may also optionally provide an initializer list of values. The newly created set will contain those values.

Usage:

Set<ValueType> set;
Set<ValueType> set = { value1, value2, value3 };

Method detail


void add(ValueType value);
Adds an element to this set, if it was not already there.

Usage:

set.add(value);

void clear();
Removes all elements from this set.

Usage:

set.clear();

bool contains(ValueType value) const;
Returns true if the specified value is in this set.

Usage:

if (set.contains(value)) ...

Set& difference(const Set& set2);
Removes from this set all elements that are present in set2. Returns a reference to this set, which has been modified in place. If you want a new set, consider set1 - set2 instead.

Usage:

set1.difference(set2);

bool equals(const Set& set2) const;
Returns true if the two sets contain exactly the same element values. Identical in behavior to the == operator.

Usage:

if (set1.equals(set2)) ...

ValueType first() const;
Returns the first value in the set when considered in sorted order. If set is empty, first signals an error.

Usage:

ValueType value = set.first();

Set& intersect(const Set& set2);
Removes from this set all elements that are not present in set2. Returns a reference to this set, which has been modified in place. If you want a new set, consider set1 * set2 instead.

Usage:

set.intersect(set2);

bool isEmpty() const;
Returns true if this set contains no elements.

Usage:

if (set.isEmpty()) ...

bool isSubsetOf(const Set& set2) const;
Returns true if every element of this set is contained in set2.

Usage:

if (set1.isSubsetOf(set2)) ...

bool isSupersetOf(const Set& set2) const;
Returns true if every element of set2 is contained in this set.

Usage:

if (set1.isSupersetOf(set2)) ...

Documented: Fall Quarter 2020


ValueType last() const;
Returns the last value in the set when considered in sorted order. If set is empty, last signals an error.

Usage:

ValueType value = set.last();

Documented: Fall Quarter 2020


void mapAll(std::function<void (const ValueType&)> fn) const;
Iterates through the elements of the set and calls fn(value) for each one. The elements are processed in sorted order.

Usage:

set.mapAll(fn);

Documented: Fall Quarter 2020


void remove(ValueType value);
Removes an element from this set. If the value was not contained in the set, there is no error and the set remains unchanged.

Usage:

set.remove(value);

int size() const;
Returns the number of elements in this set.

Usage:

int count = set.size();

string toString() const;
Returns a printable string representation of this set, such as "{value1, value2, value3}". The values are listed in sorted order.

Usage:

string str = set.toString();

Set& unionWith(const Set& set2);
Adds to this set all elements from set2. Returns a reference to this set, which has been modified in place. If you want a new set, consider set1 + set2 instead.

Usage:

set1.unionWith(set2);

Operator detail


for (ValueType elem : set)
The range-based for loop can be used to iterate through the elements in a collection. The elements in a set are accessed in sorted order. An error is signaled if you attempt to add/remove elements from a collection while iterating over it.

Usage:

for (ValueType elem : set) {
	cout << elem << endl;
}

Documented: Fall Quarter 2020


bool operator==(const Set& set2) const;
Returns true if set1 and set2 contain the same elements.

Usage:

set1 == set2

bool operator!=(const Set& set2) const;
Returns true if set1 and set2 are different.

Usage:

set1 != set2

Set operator+(const Set& set2) const;
Set operator+(ValueType element) const;
Creates a new set which is the union of set1 with set2 (or with the single value).

Usage:

set1 + set2
set1 + value

Set operator*(const Set& set2) const;
Creates a new set which is the intersection of set1 and set2.

Usage:

set1 * set2

Set operator-(const Set& set2) const;
Set operator-(ValueType value) const;
Creates a new set which is the difference of set1 minus set2 (or minus the single value).

Usage:

set1 - set2
set1 - value

Set& operator+=(const Set& set2);
Set& operator+=(ValueType value);
Adds all of the elements from set2 (or the single value) to set1.

Usage:

set1 += set2;
set1 += value;

Set& operator*=(const Set& set2);
Removes any elements from set1 that are not present in set2.

Usage:

set1 *= set2;

Set& operator-=(const Set& set2);
Set& operator-=(ValueType value);
Removes the all elements in set2 (or the single value) from set1.

Usage:

set1 -= set2;
set1 -= value;

ostream& operator<<(const Set& set);
Outputs the contents of set to the given output stream. The output is in the form {value1, value2, value3} where elements are listed in sorted order.

Usage:

cout << set << endl;

Documented: Fall Quarter 2020


istream& operator>>(Set& set);
Reads the contents of the given input stream into set. Any previous contents of the set are replaced. The input is expected to be in the form {value1, value2, value3}. If unable to read a proper set from the stream, the operation results in a stream fail state.

Usage:

if (infile >> set) ...

Documented: Fall Quarter 2020