#include <iostream>
 
template<typename T, typename... Args>
void printf(const char *s, T value, Args... args)
{
    while (*s) {
        if (*s == '%') {
            if (*(s + 1) == '%') {
                ++s;
            }
            else {
                std::cout << value;
                printf(s + 1, args...); // call even when *s == 0 to detect extra arguments
                return;
            }
        }
        std::cout << *s++;
    }
}
 
int main() {
	printf("test % %", "String", 10);
	return 0;
}

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