//----------------------------- private --------------------------------------
unsigned int Student::parseRegNr(string reginput) {
unsigned int r = 0;
for (unsigned int i = 0; i < reginput.length(); i++) {
// numbers are between ASCII code 30 and 39 hex
if (reginput[i] >= 0x30 && reginput[i] <= 0x39) {
// substract 0x30 from the input gives the
// value of the current decimal digit
// this result is then added to the number
r += reginput[i] - 0x30;
// decimal left shift the number by one decimal digit
// = multiplication by 10
if (i < reginput.length() - 1) {
r *= 10;
}
} else {
return r;
}
}
return r;
}