This code makes no sense to me, for example
for (byte i = 0; i <= 35; i++) {
char c = inputString[i];
if (c == 'V') {
int index = inputString.indexOf("V");
The for-loop and if statement seem to be searching through the string for a "V" character, one position at a time. But then you use .indexOf(), which will find the "V" in a single step, so why bother with the for-loop? It is repeating code 35 times over when it needs to run only once.