DFS by Color

#include<bits/stdc++.h>
using namespace std;
string color[100000] = "white";
int timee = 0;
int d[100000],f[100000];
class Node{
public:
    int destination;
    int weight;
    Node *next;
};
class Integer{
public:
    Node *head = NULL;
};

void addEdge(Integer arr[],int sorc,int dest)
{
    Node *newNode = new Node();
    newNode->destination = dest;
    newNode->next = NULL;
    if( arr[sorc].head == NULL)
        arr[sorc].head = newNode;
    else
    {
        Node *temp = arr[sorc].head;
        while(temp->next != NULL)
            temp = temp->next;
        temp->next = newNode;
    }
}
void DFS_Visit(Integer arr[],int s,int prev[])
{
    color[s] = "Gray";
    timee++;
    d[s] = timee;
    Node *temp = arr[s].head;
    cout<<s<< " "<<endl;
    while( temp!=NULL)
    {
        int child = temp->destination;
        if( color[child] == "white")
        {
            prev[child] = s;
            DFS_Visit(arr,child,prev);
        }
        temp = temp->next;
    }
    color[s] = "Black";
    timee = timee+1;
    f[s] = timee;
}
void DFS(Integer arr[],int prev[],int v){
    for(int i=1; i<=v; i++)
    {
        if(color[i] == "white")
            DFS_Visit(arr,i,prev);
    }
}
int main()
{
    int prev[100000] = {0};
    freopen("input.txt","r",stdin);
    int v;
    cin>>v;
    Integer arr[v];

    /// eita na korle arr er vitore v+1 dite hobe
     for (int i = 0; i <= v; i++)
        arr[i].head = NULL;

    /// getting input
    int m,n;
    while(scanf("%d%d",&m,&n) == 2)
    {
        addEdge(arr,m,n);
        //addEdge(arr,n,m);
    }
    DFS(arr,prev,v);
    cout<<d[7]<<" "<<f[7]<<" "<<prev[7]<<endl;
}