Problem 8.1.1. Dima and Seryozha were picking berries from a raspberry bush, on which 900 berries grew. Dima alternated his actions while picking: he put one berry in the basket and ate the next one. Seryozha also alternated: he put two berries in the basket and ate the next one. It is known that Dima picks berries twice as fast as Seryozha. At some point, the boys had picked all the raspberries from the bush.

Who of them ended up putting more berries in the basket? What will the difference be?