B-bank issues ATM cards with a four-digit PIN code that does not contain the digit 0. Mr. Sclerosis was afraid he would forget the PIN code of his card, so he wrote it directly on it, but in Roman numerals IIIVIIIXIV, to make it harder for a potential thief. He revealed his idea to his best friend, Mr. Odkoukal, who was also a client of B-bank. Soon, Mr. Odkoukal did the same with his PIN code and wrote IVIIIVI on his card. To his great surprise, however, he could not determine his PIN code exactly from the Roman numeral notation.

1. What is the PIN code on Mr. Sclerosis's card?
2. What PIN code could Mr. Odkoukal's card have?
1. The only way to split IIIVIIIXIV into four Roman numerals with a single-digit decimal representation is III VII IX IV. Therefore, Mr. Sclerosis has the PIN 3794.

2. Mr. Odkoukala's notation IVIIIVI allows for various interpretations; we will systematically list all possibilities:

- I V III VI, i.e., PIN $=1536$,
- I VI II VI, i.e., PIN $=1626$,
- I VII I VI, i.e., PIN $=1716$,
- I VII IV I, i.e., PIN $=1741$,
- I VIII V I, i.e., PIN $=1851$,
- IV I II VI, i.e., PIN $=4126$,
- IV II I VI, i.e., PIN $=4216$,
- IV II IV I, i.e., PIN $=4241$,
- IV III V I, i.e., PIN $=4351$.