fold_the_template

#include <iostream>
#include <string>

using namespace std::string_literals;

void tprintf(const char* format) // base function
{
    std::cout << format;
}
 
template<typename T, typename... Targs>
void tprintf(const char* format, T value, Targs... Fargs) // recursive variadic function
{
    for ( ; *format != '\0'; format++ ) {
        if ( *format == '%' ) {
           std::cout << value;
           tprintf(format+1, Fargs...); // recursive call
           return;
        }
        std::cout << *format;
    }
}

template <typename T>
auto add(T value) // base function
{
    return value;
}
 
template<typename T, typename... Targs>
auto add(T value, Targs... Fargs) // recursive variadic function
{
    return value + add(Fargs...);
}

int main()
{
    tprintf("% world% %\n","Hello",'!',123);
    int val = add(1, 3, 12);
    std::cout << val << "\n";
    auto str_val = add("the"s, ' ', "song"s, ' ', "is"s, ' ', "beautiful"s);
    std::cout << str_val << "\n";
    
    return 0;
}