Update test/factorials.jl

inkydragon · web-flow · commit 6781949fef37 · 2025-05-01T20:57:34.000+08:00
diff --git a/test/factorials.jl b/test/factorials.jl
@@ -10,6 +10,8 @@
 
     # derangement
     @test derangement(4) == subfactorial(4) == 9
+    @test derangement(0) == 1
+    @test derangement(1) == 0
     @test derangement(24) == parse(BigInt, "228250211305338670494289")
     @test_throws DomainError derangement(-1)
 
