A 1 B 2 C 3d4e5f6g7h8i9j10k11l12m13 2025. For example, a is the first letter, so it is represented by 1, b is the second letter, so it is represented by 2, and so. $converter = array('a' => '01', 'b' => '02'.);

So (a + b + c + d) is further 1 less than d so taking the above example, it will go down one step further and be 0. The code given is based on the position of the letters in the english alphabet.