DSU for Union Find in C

Data Structures/UnionFind/C/DSU.c

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+#include<iostream>
+#include<stdlib.h>
+using namespace::std;
+
+
+int *array; // array representing the parents
+int *rank; // array representing the ranks
+
+int get_parent(int index)
+{
+	int parent;
+	// TODO
+	if(array[index]==index) return index;
+	else
+	{
+		parent = get_parent(array[index]);
+		if(array[index]!=parent)
+		{
+			rank[array[index]]-=1+rank[index];
+		}
+		array[index]=parent;
+	}
+	return parent;
+}
+
+void make_DSU(int n)
+{
+	array = (int*)malloc(n*sizeof(int));
+	rank = (int*)malloc(n*sizeof(int));
+	for(int i=0;i<n;++i)
+	{
+		array[i]=i;
+		rank[i]=0;
+	}
+}
+bool find_connected(int i,int j)
+{
+	return get_parent(i)==get_parent(j);
+}
+void quick_union(int i,int j)
+{
+	if(find_connected(i,j))return; // same set already
+	else
+	{
+		if(get_parent(i) > get_parent(j) || (get_parent(i)==get_parent(j) && i>j) )
+		{
+			array[get_parent(j)] = get_parent(i);
+			rank[get_parent(i)]+=1+rank[get_parent(j)];
+		}
+		else
+		{
+			array[get_parent(i)] = get_parent(j);
+			rank[get_parent(j)]+=1+rank[get_parent(i)];
+		}
+	}
+	return;
+}
+
+
+int main() // driver to test
+{
+	make_DSU(5);
+	cout<<find_connected(2,3)<<endl; //false
+	quick_union(2,4); // 2 is child of 4
+	quick_union(3,1); // 1 is child of 3
+	cout<<find_connected(2,4)<<endl; //true
+	cout<<find_connected(2,1)<<endl; //false
+	quick_union(0,2); // 0 is child of 4
+	cout<<find_connected(0,4)<<endl; //true
+	quick_union(1,2); // 1 union 2
+	cout<<find_connected(1,4)<<endl; // true
+
+}