BFS with Adjacency List!

[mayaniak]

Hi everyone, I have created an adjacency list and I want to apply the BFS.
Anybody can help? Thanks in advance!

#include<stdlib.h>
#include<iostream>

using namespace std;

class Vertex
{
      friend class List;
      
      int value;
      Vertex *next;
      Vertex *end;
      
      Vertex() {value= 0; next=NULL; end=NULL;}
      void setValue(int node) {value=node;}          
      int getValue() {return value;}
      void ptrNext(Vertex *ptr) {next=ptr;}              
      Vertex *getNext() {return next;}           
      void ptrEnd(Vertex *ptr) {end=ptr;}               
      Vertex *getEnd() {return end;}
};

class List {
      Vertex *first;
      Vertex *last;
      
public:
      List() {first=NULL; last=NULL;}
      
void makeList() {
            int node;
            
            Vertex *newNode;
            Vertex *lastNode; 
            
            cout<<"\n Insert Node: ";
            cin>>node;
            newNode=new Vertex;
            newNode->setValue(node);
            
            if(first==NULL) {
                 first=newNode;
                 last=newNode;
            }
            else {
                lastNode=first;
                while((lastNode->getEnd()!=NULL)&&(lastNode->getValue()!=node)) {
                     lastNode=lastNode->getEnd();                                
                }                                                      
                if(lastNode->getValue()!=node) {
                     last->ptrEnd(newNode);      
                     last=newNode;          
                }
                else {
                    cout<<"\n The inserted node is already present!";
                }
            }                     
}

void setAdj() {
               Vertex *adjValue, *currentNode, *lastAdj;
               int adjNode;
               int flag;
               
               if(first==NULL) {
                    cout<<"\n There aren't any nodes!\n";                 
               }
               else {               
                    currentNode=first;
                    while(currentNode!=NULL) {
                         cout<<"\n Insert the adjacencies of "<<currentNode->getValue()<<"\n  ";                      
                         lastAdj=currentNode;
                         system("cls");
                         cout<<"\n 0: Go to the next node!";
                         cout<<"\n 1: Continue with the adjacencies of "<<currentNode->getValue()<<": ";
                         cin>>flag;
                    if(flag==1) {
                         cout<<"\n Insert the adjacent node: ";
                         cin>>adjNode;
                         adjValue=new Vertex;
                         adjValue->setValue(adjNode);                          
                         if((lastAdj->getNext()==NULL)&&(currentNode->getValue()!=adjNode)) {
                              lastAdj->ptrNext(adjValue);                                 
                              lastAdj=adjValue;           
                         }        
                         else {  
                              while((lastAdj->getNext()!=NULL)&&((lastAdj->getValue()!=adjNode)&&(currentNode->getValue()!=adjNode))) {
                                   lastAdj=lastAdj->getNext();  
                              }
                              if((currentNode->getValue()==adjNode)||(lastAdj->getValue()==adjNode)) {
                                   cout<<"\n The inserted node was already declared as adjacent!";
                              }
                              else {
                                   lastAdj->ptrNext(adjValue); 
                                   lastAdj=adjValue;     
                              }       
                         }            
                    }
                    else {
                         currentNode=currentNode->getEnd(); 
                    }        
                    } 
               }         
}

void printList() {
            Vertex *node, *adj;
             
            node=first;
            
            if(first==NULL) {
                 cout<<"\n The graph is empty!\n";
            }
            else {
                 cout<<"\n Adjacency list:\n ";
            while(node!=NULL) {
                 cout<< "\n"<< node->getValue()<< " --- ";
                 adj=node->getNext();            
                 while(adj!=NULL) {
                      cout<<adj->getValue()<<" ";
                      adj=adj->getNext(); 
                 }
                node=node->getEnd();  
            }
            }
}                         
};

int main() {
    int choice;
    List call;
    
    do
    {
    cout<<"\n\n 1: Insert node!";
    cout<<"\n 2: Set adjacency!";
    cout<<"\n 3: Print adjacency list!";
    cout<<"\n 4: Exit!";
    cout<<"\n\n Choice: ";
    cin>>choice;
    
    switch(choice)
    {
                  case 1:
                       system("cls");
                       call.makeList();
                       break;
                  case 2:
                       system("cls");
                       call.setAdj();
                       break;
                  case 3: 
                       system("cls");
                       call.printList();
                       break;
                  case 4:
                       break;     
    }
    } while(choice!=4);
}

[D80DSL3A]

You forgot to describe the problem. What is the program supposed to do? What errors are you getting?

[mayaniak]

There are no errors.
I made the adjacency list (with dynamic values) and now I want to visit the graph using BFS, but I don't know where to start from!