C++ Programming Code Examples
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To solve josephus problem using circular queue and templates
/* To solve josephus problem using circular queue and templates */
//////////////////Header file
#include<iostream.h>
template <class T>
class ex
{
private:
struct node
{
T data;
struct node *next;
};
struct node *head,*front,*rear;
public:
ex()
{
head=new node;
head->next=NULL;
front=rear=head;
}
void enqueue(T x);
T dequeue();
void print();
void move_next();
};
//////////////////Implementation file
#include "ex.h"
template <class T>
void ex<T>::enqueue(T x)
{
node *p;
p=new node;
p->data=x;
if(head->next==NULL)
{
front=rear=p;
head->next=p;
p->next=p;
}
else
{
rear->next=p;
p->next=front;
rear=rear->next;
}
}
template<class T>
T ex<T>::dequeue()
{
node *t;
T x;
t=front;
x=t->data;
front=front->next;
rear->next=front;
delete(t);
return x;
}
template<class T>
void ex<T>::print()
{
node *p=front;
do
{
cout<<p->data<<endl;
p=p->next;
}while(p!=rear->next);
}
template<class T>
void ex<T>::move_next()
{
front=front->next;
rear=rear->next;
}
/////////////////Application file
#include "ex.cpp"
void main()
{
ex<int> e;
int m,n,i,d;
cout<<"Enter the number of people
";
cin>>n;
cout<<"Enter the number of passes
";
cin>>m;
for(i=1;i<=n;i++)
e.enqueue(i);
cout<<"The players are
";
e.print();
cout<<"Eliminated in order
";
while(n>1)
{
for(i=1;i<=m;i++)
e.move_next();
d=e.dequeue();
cout<<d<<endl;
n--;
}
d=e.dequeue();
cout<<"Winning player: "<<d<<endl;
}
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