DS - HW#1

#include <iostream>


using namespace std;

int n=5;
int current_size = 0;


class student {

public:
    int ID;
    string first_name;
    string last_name;
    int age;
    student(int ID , string first_name , string last_name , int age);
    student(){};

};

student::student(int ID , string first_name , string last_name , int age)
{
    this->ID = ID;
    this->first_name = first_name;
    this->last_name = last_name;
    this->age = age;
}


bool isFull()
{
    if(current_size < n) return false;
    else return true;
}

bool isEmpty()
{
    if(current_size > 0) return false;
    else return true;
}


void Increase_Array_Size(student* &arr)
{
          student* temp_array = new student[n+5];

        for(int i=0 ; i<n ; i++)
            { // copy old elements
                temp_array[i].ID = arr[i].ID;
                temp_array[i].first_name = arr[i].first_name;
                temp_array[i].last_name = arr[i].last_name;
                temp_array[i].age = arr[i].age;

            }

            delete [] arr;

            arr = temp_array;
            n+=5;
}



void Decrease_Array_Size(student* &arr)
{
          student* temp_array = new student[n-1];

        for(int i=0 ; i<n-1 ; i++)
            { // copy old elements
                temp_array[i].ID = arr[i].ID;
                temp_array[i].first_name = arr[i].first_name;
                temp_array[i].last_name = arr[i].last_name;
                temp_array[i].age = arr[i].age;

            }

            delete [] arr;

            arr = temp_array;
            n-=1;
}


int Find_Student(student* &arr,int ID)
{
        for(int i=0; i<current_size ; i++)
            if(arr[i].ID == ID) return i;

return -1;
}


void Add_Student(student* &arr , student newStudent)
{
    if(isFull())
    {
        Increase_Array_Size(arr);
    }

    arr[current_size] = newStudent;
    current_size++;

}

bool Delete_Student(student* &arr , int studentIndex)
{
    if(isEmpty())
    {
        return false;
    }


    for(int i=studentIndex; i<current_size-1 ; i++) // left shift to ignore Last element and delete it
    {

        arr[i] = arr[i+1];

    }

    current_size--;

    Decrease_Array_Size(arr);

    return true;

}

bool Edit_Student(student* &arr , student &anStudent,int ID , string new_first_name , string new_last_name , int age)
{
    if(Find_Student(arr,ID) != -1) return false; // new id is already exist


 anStudent.ID = ID;
 anStudent.first_name = new_first_name;
 anStudent.last_name = new_last_name;
 anStudent.age = age;

 return true;
}

void Print_Students(student *arr)
{

    if(current_size < 1)
    {
        cout<<"\nList Is Empty !!!\n\n";
        return;
    }

    for(int i=0; i<current_size ; i++)
    {
        cout<<"Student ID: "<<arr[i].ID<<"\nStudent First Name: "
        <<arr[i].first_name<<"\nStudent Last Name: "
        <<arr[i].last_name<<"\nStudent Age: "
        <<arr[i].age<<"\n\n";

    }
}






int main()
{

    student *students_list = new student[n];


    int choice = -1;

    student tempStudent;

    do{

            cout<<"\n\n######## Students Manager V1 ########\n\n"
            <<"1-Add new student\n"
            <<"2-Edit exist student\n"
            <<"3-Delete exist student\n"
            <<"4-Find exist student\n"
            <<"5-Print All Students\n"
            <<"6-Exit\n\n"
            <<"Enter Your Choice ==> ";

            cin>>choice;

            switch(choice)
            {
            case (1):{


                cout<<"Enter Student ID: ";
                cin>>tempStudent.ID;

                while(Find_Student(students_list,tempStudent.ID) != -1)
                {
                    cout<<"This ID is already in list \nPlease Enter Valid ID: ";
                    cin>>tempStudent.ID;
                }

                cout<<"Enter Student First Name: ";
                cin>>tempStudent.first_name;

                cout<<"Enter Student Last Name: ";
                cin>>tempStudent.last_name;

                cout<<"Enter Student Age: ";
                cin>>tempStudent.age;

                Add_Student(students_list,tempStudent);

                cout<<"\nStudent Added Succefully !\n\n";

            break;}

            case (2):{


                cout<<"Enter Student ID: ";
                cin>>tempStudent.ID;

                int search_result = Find_Student(students_list,tempStudent.ID);

                if(search_result == -1)
                    {cout<<"This Student Dosn't Exist !!\n\n";}
                else
                    {
                        cout<<"Enter New Student Details:\n"
                          <<"ID ["<<students_list[search_result].ID <<"] ==> ";
                          cin>>students_list[search_result].ID;

                        cout<<"First Name ["<<students_list[search_result].first_name <<"] ==> ";
                          cin>>students_list[search_result].first_name;

                        cout<<"Last Name ["<<students_list[search_result].last_name <<"] ==> ";
                          cin>>students_list[search_result].last_name;

                        cout<<"Age ["<<students_list[search_result].age <<"] ==> ";
                          cin>>students_list[search_result].age;
                    }

            break;}


            case (3):{

                cout<<"Enter Student ID: ";
                cin>>tempStudent.ID;

                int search_result = Find_Student(students_list,tempStudent.ID);

                if(search_result == -1)
                    {cout<<"This Student Dosn't Exist !!\n\n";}
                else
                    {
                        Delete_Student(students_list,search_result);
                        cout<<"Student at location ["<<search_result<<"] Have Been Deleted !!\n\n";
                    }


            break;}

            case (4):{

                cout<<"Enter Student ID: ";
                cin>>tempStudent.ID;

                int search_result = Find_Student(students_list,tempStudent.ID);

                if(search_result == -1)
                    {cout<<"This Student Dosn't Exist !!\n\n";}
                else
                    {
                        cout<<"Student Details:\n"
                          <<"ID => "<<students_list[search_result].ID <<endl
                          <<"First Name => "<<students_list[search_result].first_name <<endl
                          <<"Last Name => "<<students_list[search_result].last_name <<endl
                          <<"Age => "<<students_list[search_result].age <<"\n\n";
                    }

            break;}

            case (5):{
                Print_Students(students_list);
            break;}

            case (6):{
                cout<<"Good Bye !!!\n";
            break;}

            default:
                cout<<"This option not exist !!!\n";
            }


    } while(choice != 6);


    delete []students_list;
    return 0;
}