C++ Brain Teasers

Puzzle 13

A Constant Struggle

a-constant-struggle.cpp

#include <iostream>
#include <type_traits>

template <typename T>
void byValue(T t)
{
    std::cout << std::is_const_v<T>; // true if T is const
}

template <typename T>
void byReference(T &t)
{
    std::cout << std::is_const_v<T>; // true if T is const
}

int main()
{
    int nonConstInt = 0;
    const int constInt = 0;

    byValue(nonConstInt);
    byValue(constInt);

    byReference(nonConstInt);
    byReference(constInt);
}

Guess the Output
	Try to guess what the output is before moving to the next page.

The program displays the following output:

0001

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