Data update

Task/Josephus-problem/Pluto/josephus-problem.pluto

@@ -0,0 +1,34 @@
+local fmt = require "fmt"
+
+local function josephus(n, k, m)
+    if k <= 0 or m <= 0 or n <= k or n <= m then
+         error("one or more parameters are invalid")
+    end
+    local killed = {}
+    local survived = {}
+    for i = 1, n do survived[i] = i - 1 end
+    local start = k
+    while true do
+        local finish = #survived
+        local i = start
+        local deleted = 0
+        while i <= finish do
+            killed:insert(survived:remove(i - deleted))
+            if #survived == m then return {survived, killed} end
+            ++deleted
+            i += k
+        end
+        start = i - finish
+    end
+    return {survived, killed}
+end
+
+local triples = { {5, 2, 1}, {41, 3, 1}, {41, 3, 3} }
+for triples as triple do
+    local [n, k, m] = triple
+    print($"Prisoners = {n}, Step = {k}, Survivors = {m}")
+    local sk = josephus(n, k, m)
+    print($"Survived   : {fmt.swrite(sk[1])}")
+    print($"Kill order : {fmt.swrite(sk[2])}")
+    print()
+end