make function recursive

notebooks/problem0030.ipynb

@@ -21,24 +21,51 @@
    "metadata": {},
    "outputs": [
     {
-     "name": "stdout",
-     "output_type": "stream",
-     "text": [
-      "443839\n"
-     ]
+     "data": {
+      "text/plain": [
+       "{4150, 4151, 54748, 92727, 93084, 194979}"
+      ]
+     },
+     "execution_count": 1,
+     "metadata": {},
+     "output_type": "execute_result"
     }
    ],
    "source": [
+    "from functools import cache\n",
+    "\n",
+    "@cache\n",
     "def F(n, p):\n",
-    "    total = 0\n",
-    "    while n != 0:\n",
-    "        total += (n % 10) ** p\n",
-    "        n //= 10\n",
+    "    q = n // 10\n",
+    "    if q == 0:\n",
+    "        return n ** p\n",
     "    \n",
-    "    return total\n",
+    "    return (n % 10) ** p + F(q, p)\n",
     "\n",
     "\n",
-    "print(sum(n for n in range(2, 354295) if n == F(n, 5)))"
+    "pdis = {n for n in range(2, 354295) if n == F(n, 5)}\n",
+    "pdis"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 2,
+   "id": "bda685a5",
+   "metadata": {},
+   "outputs": [
+    {
+     "data": {
+      "text/plain": [
+       "443839"
+      ]
+     },
+     "execution_count": 2,
+     "metadata": {},
+     "output_type": "execute_result"
+    }
+   ],
+   "source": [
+    "sum(pdis)"
    ]
   },
   {