@@ -114,33 +114,33 @@ public String toString() {
114114// CONSTRUCTION: with int representing initial number of sets
115115//
116116// ******************PUBLIC OPERATIONS*********************
117- // void union(root1, root2) --> Merge two sets
118- // int find( x ) --> Return set containing x
117+ // void union(root1, root2) --> Merge two sets
118+ // int find(x ) --> Return set containing x
119119// ******************ERRORS********************************
120120// No error checking is performed
121121// http://users.cis.fiu.edu/~weiss/dsaajava3/code/DisjSets.java
122122
123123/**
124- * Disjoint set class, using union by rank and path compression.
125- * Elements in the set are numbered starting at 0.
124+ * Disjoint set class, using union by rank and path compression
125+ * Elements in the set are numbered starting at 0
126126 * @author Mark Allen Weiss
127127 */
128128class DisjointSet {
129- private int [] s ; //the set field
130- 129+ private int [] set ; //the disjoint set as an array
131130
132131 public int [] getSet (){ //mostly debugging method to print array
133- return s ;
132+ return set ;
134133 }
135134
136135 /**
137136 * Construct the disjoint sets object.
138137 * @param numElements the initial number of disjoint sets.
139138 */
140- public DisjointSet ( int numElements ) { //constructor creates singleton sets
141- s = new int [ numElements ];
142- for ( int i = 0 ; i < s .length ; i ++ ) //initialize to -1 so the trees have nothing in them
143- s [ i ] = -1 ;
139+ public DisjointSet (int numElements ) { //constructor creates singleton sets
140+ set = new int [numElements ];
141+ for (int i = 0 ; i < set .length ; i ++){ //initialize to -1 so the trees have nothing in them
142+ set [i ] = -1 ;
143+ }
144144 }
145145
146146 /**
@@ -150,13 +150,15 @@ public DisjointSet( int numElements ) { //constructor creates singleton sets
150150 * @param root1 the root of set 1.
151151 * @param root2 the root of set 2.
152152 */
153- public void union ( int root1 , int root2 ) {
154- if ( s [ root2 ] < s [ root1 ] ) // root2 is deeper
155- s [ root1 ] = root2 ; // Make root2 new root
153+ public void union (int root1 , int root2 ) {
154+ if (set [root2 ] < set [root1 ]){ // root2 is deeper
155+ set [root1 ] = root2 ; // Make root2 new root
156+ }
156157 else {
157- if ( s [ root1 ] == s [ root2 ] )
158- s [ root1 ]--; // Update height if same
159- s [ root2 ] = root1 ; // Make root1 new root
158+ if (set [root1 ] == set [root2 ]){
159+ set [root1 ]--; // Update height if same
160+ }
161+ set [root2 ] = root1 ; // Make root1 new root
160162 }
161163 }
162164
@@ -166,10 +168,12 @@ public void union( int root1, int root2 ) {
166168 * @param x the element being searched for.
167169 * @return the set containing x.
168170 */
169- public int find (int x ) {
170- if (s [ x ] < 0 ) //if tree has no elements, then it is its own root
171+ public int find (int x ) {
172+ if (set [ x ] < 0 ){ //if tree has no elements, then it is its own root
171173 return x ;
172- else
173- return s [ x ] = find ( s [ x ] );
174+ }
175+ else { //Recursively find the parent of
176+ return set [x ] = find (set [x ]);
177+ }
174178 }
175179}
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