YAPC::EU 2018 Glasgow Update!

Task/Knuths-algorithm-S/Phix/knuths-algorithm-s-1.phix

@@ -0,0 +1,44 @@
+enum RID, I, SAMPLE
+
+function s_of_n(sequence env, integer item)
+    integer i = env[I] + 1,
+            n = length(env[SAMPLE])
+    env[I] = i
+    if i<=n then
+        env[SAMPLE][i] = item
+    elsif n/i>rnd() then
+        env[SAMPLE][rand(n)] = item
+    end if
+    return env
+end function
+
+function s_of_n_creator(int n)
+    return {routine_id("s_of_n"),0,repeat(0,n)}
+end function
+
+function invoke(sequence env, args)
+    env = call_func(env[RID],prepend(args,env))
+    return env
+end function
+
+function test(integer n, sequence items)
+    sequence env = s_of_n_creator(n)
+    for i=1 to length(items) do
+--      env = s_of_n(env,items[i])
+        env = invoke(env, {items[i]})
+    end for
+    return env[SAMPLE]
+end function
+
+procedure main()
+    sequence items_set = tagset(9,0)
+    sequence frequencies = repeat(0,length(items_set))
+    for i=1 to 100000 do
+        sequence res = test(3, items_set)
+        for j=1 to length(res) do
+            frequencies[res[j]+1] += 1
+        end for
+    end for
+    ?frequencies
+end procedure
+main()

Task/Knuths-algorithm-S/Phix/knuths-algorithm-s-2.phix

@@ -0,0 +1,9 @@
+enum RID, I, SAMPLE, CLOSURE_LEN=$
+...
+function s_of_n_creator(int n)
+    sequence closure = repeat(0,CLOSURE_LEN)
+    closure[RID] = routine_id("s_of_n")
+    closure[I] = 0
+    closure[SAMPLE] = repeat(0,n)
+    return closure
+end function