dsu

Graph Algorithm/dsu.cpp

@@ -0,0 +1,45 @@
+class dsu{
+	public:
+		vector<int> parent;
+		vector<int> size;
+
+		dsu(int sz){
+			parent.resize(sz);
+			size.resize(sz);
+
+			for(int i = 0 ; i < sz ; i++ )
+				parent[i] = i , size[i] = 1;
+		}
+
+		int find(int n){
+			if( parent[n] == n ) return n;
+
+			return parent[n] = find( parent[n] );
+		}
+
+		int find_iterative( int n ){
+			while( parent[n] != n ){
+				n = parent[n];
+			}
+			return n;
+		}
+
+		void unite(int a, int b){
+
+			int par_a = find(a);
+			int par_b = find(b);
+
+			if( par_a == par_b )
+				return;
+
+			if( size[par_a] < size[par_b] ) swap(par_a, par_b);
+
+			size[par_a] += size[par_b];
+
+			parent[par_b] = par_a;
+		}
+
+		bool isSame(int a , int b){
+			return find(a) == find(b);
+		}
+	};