? — Roll / Deal?N: uniform draw from ⍳N. ?0: U(0,1). Pervasive.
(?6)∊⍳6 ⍝ 1x
M?N: M draws without replacement from ⍳N.
≢3?10 ⍝ 3x
≢∪3?10 ⍝ 3x
Bounds are nonnegative integers; M≤N. Exact arguments give exact integer draws.