#include <iostream>
using namespace std;
class node
{
    private:
    int data;
    node* next;

    //Constructor 
    node(int d)
    {
        data = d;
        next = NULL;
    }
    friend class list
};
class list
{
void insertAtTail(&node node*&head,int data)//function to insert new element at tail of the list
{
    if(head == NULL){
        head = new node(data);
        return;
    }
    node *tail = head;
    while(tail->next != NULL){
        tail = tail->next;
    }
    tail->next = new node(data);
}
int buildList(&node node*&head)//function to build the list.
{
    int n;
    cout<<"Enter the size of list:";
    cin>>n;
    cout<<endl;
    int a=n;
    cout<<"<span style="color:#99cc00;">Enter data of the nodes\n";
    while(n--){
        int data;
        cin>>data;
        insertAtTail(head,data);//New element will be inserted at end.
    }
    return a;
}
void printList((&node node*head)//function to print linked list.
{
    if(head == NULL){
        return;
    }
    cout<<head->data<<" ";
    printList(head->next);
}
node* append((&node node*head,int k,int n)//function to find last n nodes
{
    node*last;
    last = head;
    int i=0;
    int ok = n-k-1; 
    while(last != NULL && i<ok)
    {
        last = last -> next;
       i++;
    }
    node*second = last->next;
    last->next = NULL;
    return second;
}
}
int main() //main function
{
    int k;
    node* head = NULL;
    int n = buildList(head);
    cout<<"Linked list data: ";
    printList(head);
    cout<<"\nEnter the value of 'n': ";
    cin>>k;
    node* temp = append(head,k,n);
    cout<<"\nAfter appending the last n nodes of a linked list to the beginning of the list\n";
    cout<<"Linked list data: ";
    printList(temp);// printing last n nodes
    printList(head);//printing remaining nodes
}

C++ Online Compiler

Write, Run & Share C++ code online using OneCompiler's C++ online compiler for free. It's one of the robust, feature-rich online compilers for C++ language, running on the latest version 17. Getting started with the OneCompiler's C++ compiler is simple and pretty fast. The editor shows sample boilerplate code when you choose language as C++ and start coding!

Read inputs from stdin

OneCompiler's C++ online compiler supports stdin and users can give inputs to programs using the STDIN textbox under the I/O tab. Following is a sample program which takes name as input and print your name with hello.

#include <iostream>
#include <string>
using namespace std;

int main() 
{
    string name;
    cout << "Enter name:";
    getline (cin, name);
    cout << "Hello " << name;
    return 0;
}

About C++

C++ is a widely used middle-level programming language.

  • Supports different platforms like Windows, various Linux flavours, MacOS etc
  • C++ supports OOPS concepts like Inheritance, Polymorphism, Encapsulation and Abstraction.
  • Case-sensitive
  • C++ is a compiler based language
  • C++ supports structured programming language
  • C++ provides alot of inbuilt functions and also supports dynamic memory allocation.
  • Like C, C++ also allows you to play with memory using Pointers.

Syntax help

Loops

1. If-Else:

When ever you want to perform a set of operations based on a condition If-Else is used.

if(conditional-expression) {
   //code
}
else {
   //code
}

You can also use if-else for nested Ifs and If-Else-If ladder when multiple conditions are to be performed on a single variable.

2. Switch:

Switch is an alternative to If-Else-If ladder.

switch(conditional-expression){    
case value1:    
 // code    
 break;  // optional  
case value2:    
 // code    
 break;  // optional  
......    
    
default:     
 code to be executed when all the above cases are not matched;    
}

3. For:

For loop is used to iterate a set of statements based on a condition.

for(Initialization; Condition; Increment/decrement){  
  //code  
}

4. While:

While is also used to iterate a set of statements based on a condition. Usually while is preferred when number of iterations are not known in advance.

while (condition) {  
// code 
}

5. Do-While:

Do-while is also used to iterate a set of statements based on a condition. It is mostly used when you need to execute the statements atleast once.

do {  
 // code 
} while (condition);

Functions

Function is a sub-routine which contains set of statements. Usually functions are written when multiple calls are required to same set of statements which increases re-usuability and modularity. Function gets run only when it is called.

How to declare a Function:

return_type function_name(parameters);

How to call a Function:

function_name (parameters)

How to define a Function:

return_type function_name(parameters) {  
 // code
}