Exponentiating by squaring

candy-lang · Jul 16, 2023 · 050d047 · 050d047 · jwbot · Jul 16, 2023
1 parent 67e4d30
commit 050d047
Showing 1 changed file with 9 additions and 3 deletions.
diff --git a/packages/Core/int.candy b/packages/Core/int.candy
@@ -120,9 +120,15 @@ pow base exponent :=
  needs (is base)
  needs (is exponent)
  needs (isNonNegative exponent)
- recursive exponent { recurse exponent ->
+ recursive [base, exponent] { recurse params ->
+ [base, exponent] = params
  ifElse
- (exponent | isPositive)
- { base | multiply (recurse (exponent | subtract 1)) }
+ (exponent | equals 0)
  { 1 }
+ { 
+ ifElse
+ (exponent | isEven)
+ { recurse [Base: base | multiply base, Exponent: exponent | shiftRight 1] }
+ { base | multiply (recurse [Base: base | multiply base, Exponent: exponent | subtract 1 | shiftRight 1]) }
+ }
  }