C++ keyword: not

#include <iostream>
 
void show(bool z, const char* s, int n)
{
    const char* r{z ? " true  " : " false "};
    if (n == 0) std::cout << "┌───────────┬─────────┐\n";
    if (n <= 1) std::cout << "│ " <<s<< " │ "<<r<<" │\n";
    if (n == 1) std::cout << "└───────────┴─────────┘\n";
}
 
int main()
{
    show(not true , "not true ", 0);
    show(not false, "not false", 1);
}