DFS - seg fault problem

[JJJIrish05]

Ah good old seg faults.... Anyone getting a seg fault with

color[u->data]="gray";

in my DFS_Visit function... not sure why... probably overlooking something with these pointers and what not

here's the code:

#include <iostream>
#include <iomanip>
#include <cstdlib>

using namespace std;


int operationsCounter=0;
int ntime=0, verts, edges;
string* color = new string[1];
int* pi = new int[1];
int* d = new int[1];
int* f = new int[1];

struct Node{
  int data;
  Node* next;
};
void InsertAfter(Node *head, int value){
  if(head==NULL){
    Node* temp=NULL;
    temp = new Node;
    temp->data = value;
    temp->next = NULL;
    head = temp;
  }else{
    Node *temp = new Node;
    temp->data = value;
    temp->next = (head)->next;
    (head)->next = temp;
  }
}


void DFS_Visit(Node* u)
{
	cout << "---in DFS_Visit u=" << endl;
	cout << "---" << &u->data << endl;
  color[u->data]="gray";
  cout << "---color" << endl;
  d[u->data]=(++ntime);
  cout << "---d" << endl;
  int v=u->data;
  cout << "---DFS_Visit before while" << endl;
  while((u=u->next)!=NULL)
  {
	  cout << "---DFS_Visit in while u=" << u->data << endl;
    if (color[u->data]=="white")
    {
      pi[u->data]=v;
      DFS_Visit(u);
    }
  }
  cout << "---DFS_Visit after while" << endl;
  color[v]="black";
  f[v]=(++ntime);
}

void DFS(Node** G)
{
  for (int u=0; u<verts; u++)
  {
    color[u]="white";
    pi[u]=-1;
  }
  ntime=0;
  cout << "---DFS 1" << endl;
  for (int u=0; u<verts; u++)
  {
    if (color[u]=="white")
    {
      DFS_Visit(G[u]);
    }
  }
  cout << "---DFS 2 done" << endl;
}

void printResults()
{
  cout << "       d    f    pi " << endl;
  for (int i=0; i<verts; i++)
  {
    if(i<10)
      cout << "    " << i;
    else if(i<100)
      cout << "   " << i;
    else if(i<1000)
      cout << "  " << i;
    else
      cout << " " << i;
    if(d[i]<10)
      cout << "    " << d[i];
    else if(d[i]<100)
      cout << "   " << d[i];
    else if(d[i]<1000)
      cout << "  " << d[i];
    else
      cout << " " << d[i];
    if(f[i]<10)
      cout << "    " << f[i];
    else if(f[i]<100)
      cout << "   " << f[i];
    else if(f[i]<1000)
      cout << "  " << f[i];
    else
      cout << " " << f[i];
    if(pi[i]<10)
      cout << "    " << pi[i] << endl;
    else if(pi[i]<100)
      cout << "   " << pi[i] << endl;
    else if(pi[i]<1000)
      cout << "  " << pi[i] << endl;
    else
      cout << " " << pi[i] << endl;
    
  }
  cout << endl << endl; 
  cout << "Number of operation: " << operationsCounter << endl;
}

bool alreadyInList(Node* llist, int data)
{
	cout << "---already in list" << endl;
  if(llist==NULL)
    return false;
  else if(data==llist->data)
    return true;
  else
    return alreadyInList(llist->next, data);
}

Node** makeGraph()
{
  int u, v;
  u=0;
  v=0;
  Node** graph = new Node*[5];
  for(int i=0; i<5; i++)
  {
    graph[i]=NULL;
    InsertAfter(graph[i], i);
  }
  for(int i=0; i<edges; i++)
  {
    while(alreadyInList(graph[u], v))
    {
      u = rand() % verts;
      v = rand() % verts;
    }
    InsertAfter(graph[u], v);
  }
  return graph;
}

Node** makeSample()
{
  Node** graph = new Node*[5];
  int i=0;
  while(i<verts)
  {
    graph[i]=NULL;
    InsertAfter(graph[i], i);
	i++;
  }
  InsertAfter(graph[0], 1);
  InsertAfter(graph[1], 2);
  InsertAfter(graph[1], 3);
  InsertAfter(graph[2], 3);
  InsertAfter(graph[2], 4);
  InsertAfter(graph[4], i);
  cout << "---Sample graph made bitches." << endl;
  return graph;
}

int main()
{
  int option=0;
  while (option!=3)
  {
    cout << "Please select an option: " << endl;
    cout << "1) Run DFS on the sample graph" << endl;
    cout << "2) Run DFS on a customized random graph" << endl;
    cout << "3) Exit" << endl;
    cin >> option;
    if(option==1)
    {
      verts=5;
      edges=6;
	  color = new string[verts];
      pi = new int[verts];
      d = new int[verts];
      f = new int[verts];
      operationsCounter=0;
      DFS(makeSample());
      printResults();
    }
    if(option==2)
    {
      cout << "How many vertices would you like the graph to have?" << endl;
      cin >> verts;
      cout << "How many edges would you like the graph to have?" << endl;
      cin >> edges;
	  color = new string[verts];
      pi = new int[verts];
      d = new int[verts];
      f = new int[verts];
      operationsCounter=0;
      DFS(makeGraph());
      printResults();
    }
  }
  cout << "Thank you.  Goodbye!";
  return 0;
}