Hi. We are doing a job for the school with arduino. What we have in mind is to make an electronic lock, in which you enter a password and this allows us to open a door.
The issue is that we cannot use libraries except for the screen library and EEPROM memory. We already have the keyboard based on if and it works correctly, but what we cannot do is that when we want to enter the password we do not know how to get a value of 4 digits (password) separated in units of one thousand, one hundred, ten, unit to then compare it with the value already saved in the EEPROM.