-
Notifications
You must be signed in to change notification settings - Fork 0
/
disjoint_sets.h
66 lines (52 loc) · 1.61 KB
/
disjoint_sets.h
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
// by Wei Shi (based on code by Mark Weiss)
// last modified 09/23/16
// Modified DisjointSets data structure for use in image processing
#ifndef DISJ_SETS_H
#define DISJ_SETS_H
// DisjSets class
//
// CONSTRUCTION: with int representing initial number of sets
//
// ******************PUBLIC OPERATIONS*********************
// void union( root1, root2 ) --> Merge two sets
// int find( x ) --> Return set containing x
// ******************ERRORS********************************
// No error checking is performed
#include <iostream>
#include <unordered_map>
#include <utility>
#include <vector>
#include <unordered_set>
using namespace std;
/**
* Disjoint set class.
* Use union by rank and path compression.
* Elements in the set are numbered starting at 0.
*/
class DisjointSets
{
public:
DisjointSets();
explicit DisjointSets( size_t numElements );
//explicit DisjointSets( unsigned short numElements );
// looks for the root of x
int find( const int& x ) const;
int find( int x );
size_t size() const;
// @param index is the index of the element to check if it is in use
bool isUsed(size_t index) const;
// always use unionSets(find(x), find(y)) to find the root of x and root of y
// before unioning two sets.
void unionSets( int root1, int root2 );
void print() const;
void printGroup() const;
void printValidIndex() const;
// post-condition sets valid_index vector
void setValidIndex(vector<bool>& rhs);
const vector<int>& getDisjointSet() const;
DisjointSets& operator=(const DisjointSets& rhs);
private:
vector<bool> valid_index;
vector<int> s;
};
#endif