C++ keyword: not_eq

#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 <= 2) std::cout << "│ "      <<s<<     " │ "<<r<<" │\n";
    if (n == 2) std::cout << "└────────────────────┴─────────┘\n";
}
int main()
{
    show(false not_eq false, "false not_eq false", 0);
    show(false not_eq true , "false not_eq true ", 1);
    show(true  not_eq false, "true  not_eq false", 1);
    show(true  not_eq true , "true  not_eq true ", 2);
}