Distributing distinct objects to distinct boxes (functions) (Eachofndistinctobjectsindependentlychoosesamongrdistinctboxes→r^n)

jee-mainjee-advanced

Each of n distinct objects independently chooses among r distinct boxes → r^n

What each symbol means

SymbolWhat it stands for
nDistinct objects / domain size
rDistinct boxes / codomain size

When to use this

Boxes allowed empty unless extra constraints; objects distinguishable.