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C++ Quiz #131

Returning a Copy or a Reference From Box

hardTemplates

get() returns T by value and peek() returns const T&. After b.set("bye"), what is printed?

📄 Code

1#include <iostream>
2#include <string>
3 
4template <typename T>
5class Box {
6    T value;
7public:
8    Box(T v) : value(v) {}
9    T get() const { return value; }
10    const T& peek() const { return value; }
11    void set(T v) { value = v; }
12};
13 
14int main() {
15    Box<std::string> b("hello");
16    std::string copy = b.get();
17    const std::string& ref = b.peek();
18    b.set("bye");
19    std::cout << copy << " " << ref << "\n";
20    return 0;
21}