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Array based list c++ simple project

Array based list Implementation
What is Array based list?
  • It is a data structure that is used to store data in a single array.
  • Also known as backing array.
Advantages:
  1. They allow you to randomly access any item in list by providing constant time access to any value in array. 
Disadvantages:
  1. They cannot expand or shrink.
  2. They are not very dynamic. It means if you want to add or remove data in somewhere middle of the list you will need to shift all elements in the array either to fill the gap caused by removal of item or to make a space for inserting an item.
  3. If number of elements exceed the size of backing array then an expensive operations needs to be performed. The operation is to make a new array of size larger than previous array and shift all the elements of previous array in new array accordingly before making new insertions.
C++ project introduction
this project contains following list of functions. Every function is called by a menu option. 

  1. Create list
  2. Delete list
  3. Clear list
  4. Display list
  5. add item in list
  6. add item at particular place
  7. remove item from list
  8. remove item from particular position
  9. swap items by position
  10. find item in list
  11. find item by position
  12. copy list
  13. update item
  14. update item by position
  15. check size of list
  16. get element
  17. check if list is full
  18. check if list is empty


C++ Project Overview:


This code below can be used by beginners as a small project or assignment during semester. It contains menu based working using 19 functions. You can add more functions in it and can extend it to any level using your own customization.



/*inclusion of header files*/
#include<iostream>
#include<conio.h>
#include<stdlib.h>
#include<stdio.h>
using namespace std;
////////////////////////////////////////////
/*initialization of global variables and dynamic array */
/*By global variable we mean the variables that can be used anywhere in whole code*/
int total_size=0;                                    // shows total size of list is zero
int *list=new int[total_size];              // dynamically creating array with size ‘0’
int cs=0;                                                 //shows that current size of list is zero
int cl=-1;                                                //shows that list is not created yet,  “cl=clear”

///////////////////////////////////////////
/*declaration of functions */
/*Below Is the list of functions that we will be using in our code*/
/*00*/void menu();
/*01*/void create_list();
/*02*/void delete_list();
/*03*/void clear_list();
/*04*/void display_list();
/*05*/void add_item(int);
/*06*/void add_item_by_position(int,int);
/*07*/void remove_item();
/*08*/void remove_item_by_position();       
/*09*/void swapp_items(int,int);
/*10*/void swapp_items_by_position(int,int);
/*11*/int find_item(int);
/*12*/int find_item_by_pos(int);
/*13*/void copy_list();
/*14*/void update_item(int,int);
/*15*/void update_item_by_position(int,int);
/*16*/void check_size_of_list();
/*17*/int get_element_by_position(int);
/*18*/int isfull();
/*19*/int isempty();
//////////////////////////////////////////////////////////////////////////////////////
The function that is written below will work throughout the code to display a menu of various functions. You will be prompted to enter the corresponding number of function you want to use and move ahead.
//////////////////////////////////////////////////////////////////////////////////////
void menu()
{
   system("pause");
   system("cls"); 
   int option;
   cout<<"****welcome to list application****\n";
   cout<<"press 0  to exit\n";           //
   cout<<"press 1  to create list\n";    //
   cout<<"press 2  to delete list\n";   //
   cout<<"press 3  to clear list\n";   //
   cout<<"press 4  to display list\n";  //
   cout<<"press 5  to add item in list\n"; //
   cout<<"press 6  to add item at particular position\n"; //
   cout<<"press 7  to remove item from list\n";
   cout<<"press 8  to remove item from particular position\n";
   cout<<"press 9  to swap items\n";//
   cout<<"press 10 to swap items by position\n";//
   cout<<"press 11 to find item in list\n";   //
   cout<<"press 12 to find item by position\n";   //
   cout<<"press 13 to copy list\n";//
   cout<<"press 14 to update item\n"; //
   cout<<"press 15 to update item by position\n"; //
   cout<<"press 16 to check size of list\n"; //
   cout<<"press 17 to get element\n"; //
   cout<<"enter 18 to check if list is full\n"; //
   cout<<"enter 19 to check if list is empty\n"; //
   cout<<"enter option:";
   cin>>option;
///////////////////////////////////////////////////  
   switch(option)
   {
    case 0:
    {
    exit(0);                               //built in function to exit from program    
    }
    break;
//////////////////////////////////////////////////   
               
    case 1:      
         {          
         create_list();
         menu();
         }
    break;
/////////////////////////////////////////////////
    case 2:
         {
         delete_list();
         menu();                                       
         }
    break;
////////////////////////////////////////////////
    case 3:
         {
         clear_list();
         menu();                                      
         }
    break;
////////////////////////////////////////////////                                                             
    case 4:
         {
         display_list();
         menu();
         }
    break;
///////////////////////////////////////////////
    case 5:
         {
         int it;                                     
         if(cl==-1)
         cout<<"list is not created\n";
         else
         if(isfull()==1)
         cout<<"list is already full\n";
         else
         do
          {
           cout<<"enter item:";
           cin>>it;
           if(find_item(it)==1)
           cout<<"item is already in list\n";
           }
                     while(find_item(it)==1);
           
           add_item(it);  
           cout<<"item added successfully in list\n";    
           cs++;                        
         }
         menu();
    break;
//////////////////////////////////////////////
    case 6:
         {
         int it,pos;
         if(cl==-1)
         cout<<"list is not created\n";
         else
          do
          {
          cout<<"enter item:";
          cin>>it;
          if(find_item(it)==1)
          cout<<"item is already in list\n";
          }
          while(find_item(it)==1);
         cout<<"enter position:";
         cin>>pos;
         if(cl==1&&pos<cs)
         {
         for(int i=cs-1;i>pos-1;i--)
         {
                 list[i+1]=list[i];
         }
         add_item_by_position(it,pos);
         
         cout<<"item added successfully at pos :"<<pos<<endl;
         cs++;
         }
         else
        
         if(cl==1&&pos>=cs&&pos< total_size)
        
         {
         list[cs]=it;
         cs++;
         }
         else
         cout<<"position out of range\n";
         }
           menu();
           break;      
/////////////////////////////////////////////
    case 7:
         {
         if(cs==0)
         cout<<"list is empty\n";
         else
         if(cl==-1)
         cout<<"list is not created\n";
         else
         remove_item();
         cout<<"item is successfully removed\n";                                   
         }
         menu();
         break;
////////////////////////////////////////////
    case 8:
         {
         if(cs==0)
         cout<<"list is empty\n";
         else
         if(cl==-1)
         cout<<"list is not created\n";
         else                                 
         remove_item_by_position();
         cout<<"item successfully deleted\n";                                 
         }
         menu();
         break;
////////////////////////////////////////////
    case 9:
         {
         int it1,it2;                                  
         if(cs==0)
         cout<<"list is empty\n";
         else
         if(cl==-1)
         cout<<"list is not created\n";
         else
         do
         {
         cout<<"enter item 1: ";
         cin>>it1;
         if(find_item(it1)!=1)
         cout<<"item is not in list\n";
         }
         while(find_item(it1)!=1);
         do
         {
         cout<<"enter item 2: ";
         cin>>it2;
         if(find_item(it1)!=1)
         cout<<"item is not in list\n";
         }
         while(find_item(it2)!=1);
         swapp_items(it1,it2);
         cout<<"items successfully swapped\n";
                                           
         }
         menu();
         break;
///////////////////////////////////////////                                                
    case 10:
         {
          int pos1,pos2;                                  
         if(cs==0)
         cout<<"list is empty\n";
         else
         if(cl==-1)
         cout<<"list is not created\n";
         else
         do
         {
         cout<<"enter position 1:";
         cin>>pos1;
         }
         while(pos1<0||pos1>=cs);
         do
         {
         cout<<"enter position 2:";
         cin>>pos2;
         }
         while(pos2<0||pos2>=cs);
        
         swapp_items_by_position(pos1,pos2);
         cout<<"items successfully swapped\n";
         }
         menu();
         break;
////////////////////////////////////////////
     case 11:
         {    
         int it;
         if(cs==0)
         cout<<"list is empty\n";
         else
         if(cl==-1)
         cout<<"list is not created\n";
         else
         {
         cout<<"enter item to check its presence in list\n";
         cin>>it;
         find_item(it);
         if(find_item(it)==1)
         {
         cout<<"item is present in list";
         int i=0;
         while(list[i]!=it)
         {
         i++;
         }
         cout<<"at position "<<i<<endl;                 
         }
         else
         cout<<"item not found\n";
         }
         menu();
         }
         break;
//////////////////////////////////////////////
         case 12:
         {
         int pos;
         if(cs==0)
         cout<<"list is empty\n";
         else
         if(cl==-1)
         cout<<"list is not created\n";
         else
         {
         do
         {
         cout<<"enter position to find its item\n";
         cin>>pos;  
         }
         while(pos<0||pos>ts);
         find_item_by_pos(pos);
         }
         menu();    
         }
         break;
//////////////////////////////////////////////
         case 13:
         {
         if(cs==0)
         cout<<"list is empty\n";
         else
         if(cl==-1)
         cout<<"list is not created\n";
         else  
         copy_list();
         cout<<"list copied successfully\n";
         }
         menu();
         break;
/////////////////////////////////////////////
         case 14:
         {
          int it1,it2;   
          if(cs==0)
          cout<<"list is empty\n";
          else
          if(cl==-1)
          cout<<"list is not created\n";
          else
          {
          do
          {       
          cout<<"enter item to be updated\n";
          cin>>it1;
          if(find_item(it1)!=1)
          cout<<"item is not in list\n";
          }
          while(find_item(it1)!=1);
          do
          {
          cout<<"enter new item to be replaced\n";
          cin>>it2;
          if(find_item(it2)==1)
          cout<<"item is already in list\n";
          }
          while(find_item(it2)==1);
          update_item(it1,it2);
         }
         }
         menu();
         break;
////////////////////////////////////////////
         case 15:
         {
          int it,pos;   
          if(cs==0)
          cout<<"list is empty\n";
          else
          if(cl==-1)
          cout<<"list is not created\n";
          else
          {
           do
           {   
           cout<<"enter item:";
           cin>>it;
           if(find_item(it)==1)
           cout<<"item already present\n";
           }
           while(find_item(it)==1);
           cout<<"enter position:";
           cin>>pos;
           if(pos<cs)
           update_item_by_position(it,pos);
           else
           cout<<"item at "<<pos<<" is not available to be updated\n";
          }
             
              
         }
         menu();
         break;
///////////////////////////////////////////
         case 16:
         {
         if(cs==0)
         cout<<"list is empty\n";
         else
         if(cl==-1)
         cout<<"list is not created\n";
         else    
         check_size_of_list();
        
         }
         menu();
         break;
//////////////////////////////////////////
         case 17:
         {   
              int a,pos;
              if(cs==0)
              cout<<"list is empty\n";
              else
              if(cl==-1)
              cout<<"list is not created\n";
              else
              do
              {
              cout<<"enter position to get from list:";
              cin>>pos;
              }
              while(pos<0||pos>cs);
              a=get_element_by_position(pos);
              cout<<"here is your item from list :"<<a<<endl;
         }
         menu();
         break;
//////////////////////////////////////////
         case 18:
         {
         if(cs==0)
         cout<<"list is empty\n";
         else
         if(cl==-1)
         cout<<"list is not created\n";
         else
         if(isfull()==1)
         cout<<"list is full\n";
         else
         cout<<"list is not full\n";
         }
         menu();
         break;
/////////////////////////////////////////
         case 19:
         {
         if(cl==-1)
         cout<<"list is not created\n";
         else
         if(isempty()==1)
         cout<<"list is empty\n";
         else
         cout<<"list is not empty\n";
         }
         menu();
         break;                 
/////////////////////////////////////////                                                                  
    default:
    cout<<"invalid option\n";
    menu();
    break;
//////////////////////////////////////////   
    }   //switch closed
    }   //funtion closed

/////////////////////////////////////////////////////////////////////////////////////////////////
/*definitions of functions*/
/*////////////////////////////////////////////////////////////////////////////////////
The function below will be used to create a list. In this function you will have to dynamically create a list first. As initially the total size of list was set to zero so that user can create a list of the size of its own choice and requirement. Total size could be any but make sure that it should be greater than current size of list. After entering total size enter current size of list that should be exactly the number of items you want to insert in list.
Suppose we set total_size to 10.
And current size (cs) to 5.
To avoid any errors we have put a check while getting value from user. You’ll be prompted to enter current size again and again if it is less than 1 or exceeds total size of list. After checking your list will be dynamically created.
After creation of list you will be prompted to insert items in a list. To avoid duplication, we have put a check on each entry. Whenever you will insert item in list, [find_item()] function will run and compare all previously inserted items of list with newly inserted item. If it is different, it will be entered otherwise it will prompt again and again to enter new value/item.
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////////////////////////////////////////////////////////////////////////////////////*/
    void create_list()
     {
     int it;
     cout<<"enter total size of list:";
     cin>>total_size ;
     do
     {
     cout<<"enter current size of list:";
     cin>>cs;
     }
     while(cs<1||cs>=ts);
    
     int i=0;
     while(i<cs)
     {
       
     cout<<"enter item:";
     cin>>it;
       
     if(find_item(it)!=1)
     {
    
     list[i]=it;
     i++;
     }
     else
     cout<<"item already present\n";
     }       //while closed
     cl=1;
     }       //function closed

The function below can be considered as a heart of the code as it will work for insertion of any new entry in list to check for duplication. It will return 1 that means true if new entry of item matches already existing item in list. Otherwise it will return 0 that means false.
Working:
We will pass any item that we want to check for duplication to this function. It will start checking from them item present at first number of list till end of list. Each time it will compare the item passed to it with item at particular position. It will continue till it reaches end of list or find a duplicate item. If there is no duplicate item and function has reached end of list, it will return 0.
     
int find_item(int it)
     {
     int i;  
     for(i=0;i< total_size;i++)
         
     if(list[i]==it)
     return 1;
     }       
The function below will randomly access any item whose position you will pass to it, and then it will return you that item.
     int find_item_by_pos(int pos)
    
     {
     cout<<"item at position "<<pos<<" is "<< list[pos]<<endl; 
     return 1;
     }
/*Suppose you pass pos = 3
This function will return you 30. According to list.*/
The function below will be used to display status of list whenever needed. But before displaying it will check if list is empty? Or if list is not created yet. If any of the two options come true, it will display the message accordingly. Otherwise it will simply display a list.



     void display_list()
     {
     if(cs==0)
     cout<<"list is empty\n";
     else
     if(cl==-1)
     cout<<"list is not created\n";
     else    
     for(int i=0;i<cs;i++)
     cout<<list[i]<<endl;
     }
/*Output: After the listed you have created first by inserting 5 items, if you will run this function the output you will have will be like:
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*/
/*////////////////////////////////////////////////////////////////////////////////////
The function below will simply delete the list by giving negative value to “cl”. Must note that array can never have negative value, but if you assign it this value it means that it doesn’t exist.
///////////////////////////////////////////////////////////////////////////////////*/

     void delete_list()
     {
     if(cl==-1)
     cout<<"list is not created\n";
     else
     cl=-1;
     cout<<"list is successfully deleted\n";
     }
////////////////////////////////////////////////////////////////////////////////////
/*////////////////////////////////////////////////////////////////////////////////////
The function below will clear the list i-e only remove items from the list. By doing this, list will come to its initial form. It will exist but will be empty. We have put check before clearing the list to check if list exists or not and if it exists is it already clear or not. The function will work if list exists and contains some values otherwise it will show a default message that you already set.
///////////////////////////////////////////////////////////////////////////////////*/

     void clear_list()
     {
     if(cl==-1)
     cout<<"list is not created\n";    
     else
     if(cs==0)
     cout<<"list is already empty\n";
     else
     cs=0;
     cout<<"list is successfully cleared\n";    
     }

The function below will add item at unallocated location right after last item in list.

     void add_item(int item)
     {
      list[cs]=item;
     } 



It will add item to specific location in list. For eg you want to insert item at 7th location then,
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    void add_item_by_position(int item,int pos)     
    {
      list[pos]=item;
       
    }

This function will return 1 if current size is equal to total size     indicating list if full and there is no more space to add more item
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    int isfull()  
    {
    if(cs== total_size)
    return 1;
    else
    return -1;   
    }

This function will return 0 if current size is zero that indicates list is empty










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Cs=0                                                                                                                                  Ts

    int isempty()
    {
    if(cs==0)
    return 1;
    else
    return 0;
    }   

The function below will be used to update and item in a list . Suppose you want to update item 40 to 80 then use this function.
Before update:
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After update:

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    void update_item(int it1,int it2)
    {
   
    if(find_item(it1)==1)
    {
    int i;                    
    for(i=0;list[i]!=it1;i++)
    int a=list[i];
    list[i]=it2;
    cout<<"at"<<i<<"="<<list[i]<<endl;
    cout<<"item successfully updated\n";
    }
    else
    cout<<it1<<"is not in list\n";    
    }



The function below will be used to update and item in a list by defining position at which place you want to update an item. Suppose you want to update item 40 to 80 and 40 is at position ‘4’ then use this function, pass the position at new item to the function. The function will replace the existing value with new value at position passed as argument.
Before update:
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After update:

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////////////////////////////////////////////////////////////////////////////////////*/

    void update_item_by_position(int it,int pos)
    {
    int  a=list[pos];
    list[pos]=it;
    cout<<"item at position "<<pos<<" is successfully updated\n";
    cout<<"old item was:"<<a<<endl;
    cout<<"new item is :"<<it<<endl;   
    }       

Current size basically shows that how many items are in a list, so in order to get size of list the function below will be used that will print value of ‘Current size (cs)’.

    void check_size_of_list()
    {
    
     cout<<"current size of list is:"<<cs<<endl;
    }
The function below can be used to directly get the item present at particular position. Suppose in list below you want to get item present t position 4, so just pass number ‘4’ as argument and function will return ’40’.

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/////////////////////////////////////////////////////////////////////////////*/
   int get_element_by_position(int pos)
   {
 
   return list[pos];
    
   }    
/*///////////////////////////////////////////////////////////////////////////////////   
The function below can be used to swap any two items in a list. You have to pass the items that you want to swap. The function will first find both values in a list and then swap them. Suppose you want to swap 20 and 40 in list so.
Before swapping:
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After swapping:

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   void swapp_items(int it1,int it2)
   {
    int j=0,k=0;
   
    do
    {
    j++;
    }
    while(list[j]!=it1);
  
    do
    {
    k++;
    }
    while(list[k]!=it2);
   int temp=0;
   temp=list[j];
   list[j]=list[k];
   list[k]=temp;
   }

The function below can be used to swap any two items in a list. You have to pass the positions of items that you want to swap. This thing will give you instant result and function will not have to find the values first. It will directly go to the positions and then swap items. Suppose you want to swap items at position 2 and 4  in list so.
Before swapping:
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After swapping:

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////////////////////////////////////////////////////////////////////////////////////*/
  void swapp_items_by_position(int pos1,int pos2)
  {
    int temp=0;
    temp=list[pos1];
    list[pos1]=list[pos2];
    list[pos2]=temp;  
   }  
/*/////////////////////////////////////////////////////////////////////////////////
The function below can be used to copy list items from one list to another. 
////////////////////////////////////////////////////////////////////////////////*/
   void copy_list()
   {
    int i,j;   
    int *c_list=new int[cs];
    for(i=0;i<cs;i++)
    c_list[i]=list[i];
    cout<<"your copied list is\n";
    for(j=0;j<cs;j++)
    cout<<c_list[j]<<endl;  
    }
/*////////////////////////////////////////////////////////////////////////////////
The function below can be used to remove an item from list. You have to pass the item you want to delete. The function will first find item in list then delete it.


void remove_item()
 {
  int it;   
  do
  {
  cout<<"enter item to delete from list:";
  cin>>it;   
  if(find_item(it)!=1)
  cout<<"item is not in list\n";
  }
  while(find_item(it)!=1);
   int i=0;  
  do
  {
  i++;    
  }
  while(list[i]!=it);
  int a;
  a=list[i];
  for(int j=i;j<cs-1;j++)
  {
  list[j]=list[j+1];
  }
  cs--;
  }
/*/////////////////////////////////////////////////////////////////////////////
The function below can be used to remove an item from list. You have to pass the position from which you want to delete item. The function will go to that position in list then delete it.
//////////////////////////////////////////////////////////////////////////////*/
   void remove_item_by_position()
   {
    int pos;
    do
    {
    cout<<"enter position:";
    cin>>pos;
    if(pos<0||pos>cs)
    cout<<"there is no item at position "<<pos<<endl;   
    }
    while(pos<0||pos>cs);   
    int a;
    a=list[pos];
    for(int i=pos;i<cs;i++)
    {
     list[i]=list[i+1];
    }
    cs--;
   } 
////////////////////////////////////////////////////////////////////////////////    
/* start of main*/
////////////////////////////////////////////////////////////////////////////////////         
    int main()
    {
        menu();
        getch();
    }
/*end of main */


Download c++ source code

Sample input outputs
array based list c++ project example

Select option create list




 Display all items in list option 4

array code simple project eample



This C++ project has developed by a student and can be improve student like you. You may found bugs in it but they are meant to be solve by you. It is very good for learning to change the logic or flow of code according to your need


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