CS162 exam notes

//Cs162 exam notes

Good Practices
If a function is not changing anything, declare it const
Make getters and setters for EVERY class and USE them - this future proofs your code
Have a copy class for your classes to assign one object to another
Pass by reference whenever passing data structures
When you overload the << operator it cannot be a member function of the class (declare friend if it needs to access private info)
Only make something a friend of a class IF it needs to directly access private stuff

Pointer: int*
Dereference: *x
vector<int*> x{};
v.push_back(new int{23});
cout << *v[0] << endl;
v[0]->method(thing);
When you dynamically allocate memory you get back a pointer

Common includes/include guard
#ifndef INTEGERSET_H //include guard
#define INTEGERSET_H
#include <vector>//vector
#include <iostream> //cout
#include <stdexcept> //exceptions
#include <sstream> //ostream and ostringstream (use .str() on ostringstreams)
#endif // INTEGERSET_H //end include guard

Basic Class outline
.h file:

#ifndef WEAPON_H
#define WEAPON_H
class Weapon {
public:
    Weapon(const int);
    void setDamage(const int) const;
    int getDamage() const;
private:
    int damage;
};
#endif // WEAPON_H

.cpp file:

#include "Weapon.h"

Weapon::Weapon(const int in) {
}

void Weapon::setDamage(const int in) const {
}

int Weapon::getDamage() const {
}

Operator Overloading
object operator+(object input) {
    object result{};
    result.thing = this->thing + input.thing;
    return result;
}

std::ostream& operator<<(std::ostream& oin,Rational in) { //overloads left shift operator
    oin << in.toString();
    return oin;
}
// Define prefix increment operator.
Point& Point::operator++()
{
   _x++;
   _y++;
   return *this;
}

// Define postfix increment operator.
Point Point::operator++(int)
{
   Point temp = *this;
   ++*this;
   return temp;
}


Looping structures
for (int i = 0; i < target; i++) {
}

do {
stuff;
} while (condition);

while(condition) {
   statement(s);
}
Dynamic memory allocation:
    Array<int*,10> XXX{nullptr}; //when we use new it always gives us a pointer to an object
    XXX[0] = new int{234}; //allocates memory for a new int in this array
    Delete XXX[0]; //deletes element of array, array still exists
    XXX[0] = nullptr; //wipes memory where that element was
Errors:
#include <stdexcept>
throw std::invalid_argument(“invalid input”);
    try{
        Clock x{43201};
    }
    catch (invalid_argument& e) {
        cout << "An exception occurred I think, here's what it might say:" << e.what() << endl;
    }