adjacency list directed graph code example
Example: adjacency list representation of graph
#include <iostream>
using namespace std;
#define v 5
class node
{
public:
int data;
node*next;
};
node*adjlist[v];
void init()
{
for(int i=0;i<v;i++)
{
adjlist[i]=NULL;
}
}
void addedge(int str,int en)
{
node*temp=new node;
temp->data=en;
temp->next=adjlist[str];
adjlist[str]=temp;
}
void hasedge(int str,int en)
{
node*temp=new node;
temp=adjlist[str];
while(temp!=NULL)
{
if(temp->data==en)
{
cout<<"yes:";
}
temp=temp->next;
}
}
void remove(int str,int en)
{
if(adjlist[str]==NULL)
{
return;
}
if(adjlist[str]->data==en)
{
node*temp=new node;
temp=adjlist[str];
adjlist[str]=adjlist[str]->next;
delete temp;
}
else
{
node *ptr=new node;
ptr=adjlist[str];
while(ptr->next!=NULL)
{
node*temp=new node;
if(ptr->next->data==en)
{
temp=ptr->next;
ptr->next=ptr->next->next;
delete temp;
break;
}
ptr=ptr->next;
}
}
}
void display()
{
for(int i=0;i<v;i++)
{
node*temp=new node;
cout<<"adjlist[]"<<i<<endl;
temp=adjlist[i];
while(temp!=NULL)
{
cout<<temp->data<<" ";
temp=temp->next;
}
cout<<endl;
}
}
int main()
{
init();
addedge(0,1);
addedge(0,2);
addedge(0,3);
addedge(1,3);
addedge(1,4);
addedge(2,3);
addedge(3,4);
display();
hasedge(0,3);
hasedge(0,4);
remove(0,1);
remove(1,4);
display();
return 0;
}