// using unsigned int as a paramter to deal with with negative numbers #include "ft_printf.h" int ft_puthexupper(unsigned int n) { const char hex[16] = "0123456789ABCDEF"; int save; int remainder; int counter; remainder = 0; save = 0; counter = 0; if (n > 15) { save = n; n /= 16; remainder = save - (n * 16); counter += ft_puthexupper(n); counter += write(1, &hex[remainder], 1); } else counter += write(1, &hex[n], 1); return (counter); }