Please fix my code in the picture: In C$++$ Member function copy$\_$piece, which returns a specified substring. The function has the location as input and number of characters to read. Function call can read:

copy$\_$piece$($&text$[3],4)$;

My code: StringVar StringVar::copypiece$($int position, int length$1)\{$

if $($position $>$ length$()-1||$ position $<mtext></mtext><mn>0</mn><mi>)</mi>$

$\{$

cout $$ "You are not able to do that, exiting now...";

exit$(1)$;

$\}$

StringVar result$()$;

return result;

$\}$