Sample Task and Solution : Overloading Ostream Operator of HackerRank

 The task is to overload the << operator for Person class in such a way that for p being an instance of class Person the result of:

std::cout << p << " " << <some_string_value> << std::endl;

produces the following output:

first_name=<first_name>,last_name=<last_name> <some_string_value>

where:

• <first_name> is the value of p's first_name_
• <last_name> is the value of p's last_name_
• <some_string_value> is an arbitrary std::string value

Input Format

The input is read by the provided locked code template. In the only line of the input there are 3 space-separated strings first_name, last_name, event. The values of first_name and last_name will be used to create an object p of type Person. The value of event will be used by the provided code to produce the output.

Constraints

• Each word in the input contains only English letters and is no longer than 15 characters

Output Format

The output should be produced by the provided locked code template. This code will use the implementation of Person public methods and the overloaded << operator to produce the output. Specifically, the output wiil be produced by the following code:

cout << p << " " << event << endl;

Sample Input 0

john doe registered

Sample Output 0

first_name=john,last_name=doe registered

Solution

#include <iostream>

using namespace std;

class Person {

public:

    Person(const string& first_name, const string& last_name) : first_name_(first_name), last_name_(last_name) {}

    const string& get_first_name() const {

      return first_name_;

    }

    const string& get_last_name() const {

      return last_name_;

    }

private:

    string first_name_;

    string last_name_;

};

// Enter your code here.

ostream& operator<<(ostream& os, const Person& p) {

    os << "first_name=" << p.get_first_name() << ",last_name=" << p.get_last_name();

    return os;

}

int main() {

    string first_name, last_name, event;

    cin >> first_name >> last_name >> event;

    auto p = Person(first_name, last_name);

    cout << p << " " << event << endl;

    return 0;

}

Source : HackerRank