Adjacency list

#include<bits/stdc++.h>
using namespace std;
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 display(Integer listt[], int v)
{
    for(int i =0; i<=v; i++)
    {
        cout<<"\n Adjacency list of vertex "<<i<<" -->";
        while(listt[i].head != NULL)
        {
            cout<<" "<<listt[i].head->destination;
            listt[i].head = listt[i].head->next;
        }
    }

}
int main()
{
    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);
    }
    display(arr,v);
}

///test case:
/*
7

1 2
1 3
2 3
4 5
5 6
5 3
6 2
6 4
3 7
5 7
*/