OK so for something like this I have my string coming in and str[0] must be a letter between "A" and "G" 7 letters total and str[1] is a number between 1 and 7. how can I change this code so that it is properly checking that str[0] is only a letter between A and G while str[1] is only a number between 1 and 7.

BOARD_SIZE is a const int = 7

== if (str.size() 2) { if (str[] >= 'A' && str[0] = 0 && str[1]