Hello Guys, Hope you are at good state of health ..
i'm trying to write code to maintain a list of students.
encountered a problem i.e: Operator = is ambigous
I tried all the possibilities to rectify that, but failed, now i'm here for some help ..
#include <iostream>
#include <string>
using namespace::std;
template<class T>
class List
{
public:
List(int size);
~List();
void insert(const T value);
bool remove(const T value);
void setData(int index, T value);
T getData(int index);
int search(T key); void printArr() const;
bool isFull() const;
bool isEmpty() const;
int length() const;
List(const List& other); const List& operator=(const List& rhs); private:
bool removeAt(int index); int MaxSize; T *listArray; int mSize; string sName;
int rollNo;
};
template<class T>
List<T>::List(int size){
if (size < 0){
throw -1;
}
else
MaxSize = size;
mSize = 0;
sName = " ";
rollNo = -69;
listArray = new T[MaxSize];
if (listArray == NULL){
throw 1;
}
else{
cout << "Memory Allocated SuccessfullY .. " << endl;
for (int i = 0; i < MaxSize; i++)
{
listArray[i] = 0;
}
}
}
template<class T>
List<T>::List(const List<T>& other){ MaxSize = other.MaxSize;
mSize = other.mSize;
listArray = new T[mSize]; if (listArray == NULL)
{
throw 1;
}
for (int i = 0; i < mSize; i++)
{
listArray[i] = other.listArray[i];
}
}
template<class T>
const List<T>& List<T>::operator=(const List<T>& rhs){ if (this != &rhs)
{
MaxSize = rhs.MaxSize;
mSize = rhs.mSize;
delete listArray;
listArray = new T[mSize];
if (listArray == NULL)
{
throw 1; }
for (int i = 0; i < mSize; i++)
{
listArray[i] = rhs.listArray[i];
}
return *this;
}
else
cout << "Whatever " << endl;
}
The statement listArray[i] = 0; in the constructor cause the error ..
CODE(V1):
Here is the Problem statement:
Develop a system to store and query information about students and the courses they have taken. The information about the student includes his/her GIFT roll number and name. The course information has the course code and the GPA in that course. A student can take up to 50 courses and this information is maintained in a list. The list of students is also a list. These lists should be ordered lists.
You need to provide the following operations:
1. Create an empty list of students.
2. Add a new student to the list.
3. Delete a student from the list.
4. Add a course for a given student.
5. Delete a course for a given student.
6. Given the roll number, find if a student is present in the list. (use binary search)
7. Given the roll number, compute the CGPA of the students.
8. Given the roll number, list all the course a student has taken along with the awarded grades and GPA for each course.
9. List all the students. (complete details – student and his grades)
You have to use the ADT for list for storing the information about students and grades. In order to access the data, you must use iterator. In the process you also have to write all the necessary functions for the proper working of the system (e.g. the copy constructors and assignment operators, if needed).
I'm much frustrated regarding this, Please help me for good statrup, Please, :(
this is a new concept for me(templates, Iterators) :(
what i know is: there should be 4 classes:
class Student {...};
class Course {...};
class StudentIterator {...};
class CourseIterator {...};
where i stuck is:
what i write in <type>, actually i want to create suppose 5 Students. But how can i do that. ??? ?? ?
#include <iostream>
#include <string>
using namespace::std;
//List: A collection of elements of the same type.
template<class T>
class List // List of Students
{
public:
List(int size);
~List();
void insert(const T value);
bool remove(const T value);
void setData(int index, T value);
T getData(int index);
int search(T key); // linear search
// if found, returns index of the key
// else returns -1
void printArr() const;
bool isFull() const;
bool isEmpty() const;
int length() const;
List(const List& other); // copy constructor
const List& operator=(const List& rhs); // assignment operator
private:
bool removeAt(int index); // remove the element at a given index
int MaxSize; // max List size
T *listArray; // array to store the data
int mSize; // no. of elements in the List
string sName;
int rollNo;
};
template<class T>
List<T>::List(int size){
if (size < 0){
throw -1;
}
else
MaxSize = size;
mSize = 0;
sName = " ";
rollNo = -69;
listArray = new T[MaxSize];
if (listArray == NULL){
throw 1;
}
else{
cout << "Memory Allocated SuccessfullY .. " << endl;
/*for (int i = 0; i < MaxSize; i++)
{
listArray[i] = 0;
}*/
}
}
template <class T>
List<T>::~List(){
delete[] listArray;
}
template<class T>
void List<T>::printArr() const{
for (int i = 0; i < mSize; i++)
{
cout << *(listArray + i) << " ||";
}
cout << endl;
}
template<class T>
List<T>::List(const List<T>& other){ // Well Copy Constructor //
MaxSize = other.MaxSize;
mSize = other.mSize;
listArray = new T[mSize]; // always check for NULL ?:
if (listArray == NULL)
{
throw 1;
}
for (int i = 0; i < mSize; i++)
{
// *(listArray + i) = *(other + i)
listArray[i] = other.listArray[i];
}
}
template<class T>
//List<T>::operator=(const List<T>& rhs){
const List<T>& List<T>::operator=(const List<T>& rhs){ // Finally OverLoaded Assignment Operator =
if (this != &rhs)
{
MaxSize = rhs.MaxSize;
mSize = rhs.mSize;
delete listArray;
listArray = new T[mSize];
if (listArray == NULL)
{
throw 1; //"OUT_OF_MEMORY"
}
for (int i = 0; i < mSize; i++)
{
listArray[i] = rhs.listArray[i];
}
return *this;
}
else
cout << "Daru Desi " << endl;
}
template<class T>
bool List<T>::isEmpty()const {
return (mSize == 0);
}
template<class T>
bool List<T>::isFull()const{
return (mSize == MaxSize);
}
template<class T>
int List<T>::length()const {
return mSize;
}
template<class T>
void List<T>::insert(const T value)
{
if (isFull()) throw 2;
listArray[mSize] = value;
mSize++;
}
template<class T>
bool List<T>::remove(const T value)
{
int index = search(value);
if (index == -1) return false;
else return removeAt(index);
}
template<class T>
bool List<T>::removeAt(int index)
{
if (index < 0 || index >= mSize)
throw 3;
else
{
listArray[index] = listArray[mSize - 1];
mSize--;
return true;
}
}
template<class T>
T List<T>::getData(int index)
{
if (index < 0 || index >= mSize) throw 3;
else return listArray[index];
}
template<class T>
void List<T>::setData(int index, T value)
{
if (index < 0 || index >= mSize) throw 3;
else listArray[index] = value;
mSize++;
}
template<class T>
int List<T>::search(T key)
{
for (int i = 0; i < mSize; i++)
if (listArray[i] == key) return i;
else
return -1;
}
int main(){
try{
string name;
int id;
List<int> s_id(7);
List<string> s_name(7);
for (int i = 0; i < 5; i++)
{
cin >> name;
s_name.insert(name);
cin >> id;
s_id.insert(id);
}
cout << endl;
for (int j = 0; j < s_name.length(); j++)
{
cout << s_name.getData(j) << "\t" << s_id.getData(j) << endl;
}
}
catch (int x){
if (x == -1){
cout << "Size Should Be >= 0 ERROR CODE: -1" << endl;
}
else if (x == 1){
cout << " OUT_OF_MEMORY ERROR CODE: 1" << endl;
}
else if (x == 2){
cout << " OUT_OF_SPACE ERROR CODE: 2" << endl;
}
else if (x == 3){
cout << " ILLEGAL_INDEX ERROR CODE: 3" << endl;
}
else
cout << "Some Thing Else happened " << endl;
}
catch (...){
cout << "Whatever .. " << endl;
}
return 0;
}
Keenly waiting Your Suggestions.
-Thanks
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