string format n is an escape into utf 8 definition in c code example
Example: c escape characters
Escape HEX in ASCII Character represented
\a 07 Alert (Beep, Bell) (added in C89)
\b 08 Backspace
\e 1B Escape character
\f 0C Formfeed Page Break
\n 0A Newline (Line Feed); see notes below
\r 0D Carriage Return
\t 09 Horizontal Tab
\v 0B Vertical Tab
\\ 5C Backslash
\' 27 Apostrophe or single quotation mark
\" 22 Double quotation mark
\? 3F Question mark (used to avoid trigraphs)
\nnn any The byte whose numerical value is given by nnn interpreted as an octal number
\xhh… any The byte whose numerical value is given by hh… interpreted as a hexadecimal number
\uhhhh none Unicode code point below 10000 hexadecimal
\Uhhhhhhhh none Unicode code point where h is a hexadecimal digit