[ Evenness and Oddness ]

On five cards, natural numbers from 1 to 5 are written. Leshа and Dima took two cards each, without looking, and hid the remaining card without looking as well. After examining his cards, Leshа told Dima: "I know that the sum of the numbers on your cards is even!"; and he was right. What numbers are written on Leshа's cards?

#
Leshа sees two numbers, so he knows which three numbers are left. If he is sure that the sum of any two numbers from the remaining three is even, then these three numbers must be of the same parity (otherwise, the sum of an even and an odd number would be odd). In the given set, there are no three even numbers, so the numbers that Leshа does not see are 1, 3, and 5. Therefore, the numbers on his cards are 2 and 4.

## Answer

2 and 4.
Task