void randomClusterGraph(ClusterGraph &C,Graph &G,int cNum)
{
int n = G.numberOfNodes();
//int m = G.numberOfEdges();
node v;
int count = 0;
NodeArray<int> num(G);
Array<node> numNode(0,n-1,0);
forall_nodes(v,G)
{
num[v] = count;
numNode[count] = v;
count++;
}
// finding the number of nodes in a tree
int numNode (TreeNodePtr root){
if(root == NULL) return 0;
return 1 + numNode(root->leftPtr) + numNode(root->rightPtr);
}