C++ Modifying class object within a vector - c++

Question

My issue is my last increment_watch function. I would like to be able modify parts of the Movie class while it is in a vector container. Right now I am only able to grab a specific Movie object and its increment but I am unable to change or modify any of it while it is in a vector. I would like to be able to modify or add +1 to the watched element. Is this at all possible?
EDIT: I have updated the "increment_watched" function taking suggestions from the comments. I have tried to pass by reference the watched variable but the "mov.set_watched" call in the increment_watched function is not taking effect.
#include <iostream>
#include <vector>
#include <string>
class Movie {
friend std::ostream &operator<<(std::ostream &os, const Movie &p);
private:
std::string name;
std::string ratting;
int watched;
public:
Movie() = default;
Movie(std::string name, std::string ratting, int watched)
: name{name}, ratting{ratting}, watched{watched} {}
void increment_watched(std::vector<Movie> vec, std::string name);
bool operator<(const Movie &rhs) const { // always overload
return this->watched < rhs.watched;
}
bool operator==(const Movie &rhs) const {
return (this->name == rhs.name && this->watched == rhs.watched); // always overload
}
void set_name(std::string name) {
this->name = name;
}
std::string getName() {
return name;
}
void set_ratting(std::string ratting) {
this->ratting = ratting;
}
std::string getRatting() {
return ratting;
}
void set_watched(int watched) {
this->watched = watched;
}
int getWatched() {
return watched;
}
};
std::ostream &operator<<(std::ostream &os, const Movie &p) {
os << p.name << " : " << p.ratting << " : " << p.watched;
return os;
}
// template function to display any vector
template <typename T>
void display(const std::vector<T> &lem) {
std::cout << "[ ";
for (const auto &elem: lem)
std::cout << elem << " ";
std::cout << " ]"<< std::endl;
}
// I want to modify this function to increment the "watched" variable by one
void increment_watched(std::vector<Movie> vec, std::string name, int &watched){
watched =+ 1;
for (auto &mov: vec){
if (mov.getName() == name){
std::cout << name << std::endl;
mov.set_watched(watched);
}
}
}
int main() {
std::vector<Movie> vec;
int watched = 1;
Movie p1 {"Star Wars", "PG", 2};
Movie p2 {"Indiana Jones", "PG", 1};
Movie p3 {"Matrix", "PG-13", 5};
vec.push_back(p2);
vec.push_back(p3);
std::cout << p1.getName() << std::endl;
std::cout << p1.getRatting() << std::endl;
p1.set_watched(100);
vec.push_back(p1);
std::cout << p1.getWatched() << std::endl;
display(vec);
increment_watched(vec, "Star Wars", watched);
display(vec);
return 0;
}

Answer 1

Thank you user WhozCraig, this lead me to answering my question!
You response lead the to the correct output. I wanted to change the values and completely over looked passing the vec variable to pass by reference. I knew it was something small that I was over looking
To all those who posted helpful comments to help post better questions on the site, thank you. I am new to StackOverflow. I will review the provided helpful links in order to post better questions in the future. Some commented that I posted the same question twice, I panicked and deleted the post because it was locked, I didnt know what to do so I thought I would start over.
Here is the corrected code:
#include <iostream>
#include <vector>
#include <string>
class Movie {
friend std::ostream &operator<<(std::ostream &os, const Movie &p);
private:
std::string name;
std::string ratting;
int watched;
public:
Movie() = default;
Movie(std::string name, std::string ratting, int watched)
: name{name}, ratting{ratting}, watched{watched} {}
void increment_watched(std::vector<Movie> vec, std::string name);
bool operator<(const Movie &rhs) const { // always overload
return this->watched < rhs.watched;
}
bool operator==(const Movie &rhs) const {
return (this->name == rhs.name && this->watched == rhs.watched); // always overload
}
void set_name(std::string name) {
this->name = name;
}
std::string getName() {
return name;
}
void set_ratting(std::string ratting) {
this->ratting = ratting;
}
std::string getRatting() {
return ratting;
}
void set_watched(int watched) {
this->watched = watched;
}
int getWatched() {
return watched;
}
};
std::ostream &operator<<(std::ostream &os, const Movie &p) {
os << p.name << " : " << p.ratting << " : " << p.watched;
return os;
}
// template function to display any vector
template <typename T>
void display(const std::vector<T> &lem) {
std::cout << "[ ";
for (const auto &elem: lem)
std::cout << elem << " ";
std::cout << " ]"<< std::endl;
}
// I want to modify this function to increment the "watched" variable by one
void increment_watched(std::vector<Movie> &vec, std::string name, int &watched){
for (auto &mov: vec){
if (mov.getName() == name){
std::cout << name << std::endl;
mov.set_watched(watched + 1);
}
}
}
int main() {
std::vector<Movie> vec;
int watched = 3;
Movie p1 {"Star Wars", "PG", 2};
Movie p2 {"Indiana Jones", "PG", 1};
Movie p3 {"Matrix", "PG-13", 5};
vec.push_back(p2);
vec.push_back(p3);
std::cout << p1.getName() << std::endl;
std::cout << p1.getRatting() << std::endl;
p1.set_watched(100);
vec.push_back(p1);
std::cout << p1.getWatched() << std::endl;
display(vec);
increment_watched(vec, "Star Wars", watched);
display(vec);
return 0;
}