net.automatalib.commons.util

## Interface IntDisjointSets

• All Known Implementing Classes:
UnionFind, UnionFindRemSP

`public interface IntDisjointSets`
Interface for disjoint-set forest implementations that operate on a universe of contiguous integers.
Author:
Malte Isberner
• ### Method Summary

All Methods
Modifier and Type Method and Description
`default boolean` ```equivalent(int x, int y)```
Checks if two elements are in the same set.
`int` `find(int x)`
Determines the representative element of the set containing `x`.
`int` ```link(int rx, int ry)```
Links (unites) two sets, identified by their representatives.
`int` `size()`
Returns the size of the universe.
`default boolean` ```union(int x, int y)```
Unites the sets containing the respective elements.
• ### Method Detail

• #### size

`int size()`
Returns the size of the universe. The elements of the universe are the integers between `0` (inclusive) and `size()` (exclusive).
Returns:
the size of the universe
• #### equivalent

```default boolean equivalent(int x,
int y)```
Checks if two elements are in the same set.
Parameters:
`x` - the first element
`y` - the second element
Returns:
`true` if `x` and `y` are in the same set, `false` otherwise
• #### find

`int find(int x)`
Determines the representative element of the set containing `x`.
Parameters:
`x` - the element to find
Returns:
the representative element of the set containing `x`.
• #### union

```default boolean union(int x,
int y)```
Unites the sets containing the respective elements. If two disjoint sets were united, the return value is `true`. Otherwise, if `x` and `y` were already in the same set, `false` is returned.

Attention: this method returns `true` if and only if `equivalent(x, y)` would have returned `false`.

Parameters:
`x` - the first element
`y` - the second element
Returns:
`true` if two disjoint sets have been united as a result, `false` otherwise
```int link(int rx,
`rx` - the representative of the first set
`ry` - the representative of the second set
the representative of the resulting set (typically either `rx` or `ry`).