Add Disjoint-Sets.

Author: manosriram

Disjoint-Sets/DisjointSet.hpp

@@ -0,0 +1,50 @@
+struct Node {
+ int rank, value;
+ shared_ptr<Node> parent;
+};
+
+class DisjointSet {
+ public:
+ map<int, shared_ptr<Node> > mp;
+ void makeSet(int n) {
+ shared_ptr<Node> nK = make_shared<Node>();
+ nK->rank = 0;
+ nK->value = n;
+ nK->parent = nK;
+ mp[n] = nK;
+ return; 
+ }
+
+ shared_ptr<Node> findParentDriver(shared_ptr<Node> p) {
+ if (p->parent == p)
+ return p;
+
+ findParentDriver(p->parent);
+ return p->parent;
+ }
+
+ shared_ptr<Node> findParent(int n) {
+ shared_ptr<Node> pt = this->mp[n];
+ return findParentDriver(pt);
+ }
+
+ bool Union(int a, int b) {
+ shared_ptr nodeA = mp[a];
+ shared_ptr nodeB = mp[b];
+
+ shared_ptr parentA = findParent(a);
+ shared_ptr parentB = findParent(b);
+
+ if (parentA->value == parentB->value)
+ return false;
+
+ if (parentA->rank >= parentB->rank) {
+ parentB->parent = parentA;
+ parentB->rank = (parentA->rank == parentB->rank) ? (parentB->rank + 1) : parentB->rank;
+ } else {
+ parentA->parent = parentB;
+ }
+ return true;
+ }
+};
+

Disjoint-Sets/Main.cpp

@@ -0,0 +1,18 @@
+#include <map>
+#include <iostream>
+using namespace std;
+#include "DisjointSet.hpp"
+
+int main() {
+ DisjointSet *ds = new DisjointSet();
+
+ ds->makeSet(1);
+ ds->makeSet(2);
+ ds->makeSet(3);
+ ds->makeSet(4);
+
+ ds->Union(1, 2);
+
+ cout << ds->findParent(2).get()->value << endl;
+}
+