rod cutting and memoization is working.

nlopt · Oct 26, 2023 · 671ad22 · 671ad22
1 parent 515baaa
commit 671ad22
Showing 1 changed file with 92 additions and 27 deletions.
diff --git a/AstrosSuck.ipynb b/AstrosSuck.ipynb
@@ -4,7 +4,7 @@
   "metadata": {
     "colab": {
       "provenance": [],
-      "authorship_tag": "ABX9TyPtE9KzkDB5CD9eVNkgZRAz",
+      "authorship_tag": "ABX9TyOAmJRrll3WB5UfByEwYzIO",
       "include_colab_link": true
     },
     "kernelspec": {
@@ -398,7 +398,7 @@
       "metadata": {
         "id": "GLxFdoVBWNP1"
       },
-      "execution_count": 6,
+      "execution_count": null,
       "outputs": []
     },
     {
@@ -413,7 +413,7 @@
         "id": "WfbetcEjeEPG",
         "outputId": "03a44a55-7cdc-4eb9-9994-80017b62e986"
       },
-      "execution_count": 7,
+      "execution_count": null,
       "outputs": [
         {
           "output_type": "execute_result",
@@ -441,67 +441,132 @@
     {
       "cell_type": "code",
       "source": [
-        "p = [1,5,8,9,10]"
+        "p = [0,1,5,8,9,10,17,17,20,24,30]"
       ],
       "metadata": {
         "id": "eoVRbaHkeKIG"
       },
-      "execution_count": 17,
+      "execution_count": 51,
       "outputs": []
     },
     {
       "cell_type": "code",
       "source": [
         "def RodCutting(p,l):\n",
-        "  if l<=0:\n",
+        "  if l==0:\n",
         "    return 0\n",
         "  else:\n",
-        "   return max((p[i]+RodCutting(p,l-i) for i in range(l)))"
+        "   return max(p[i]+RodCutting(p,l-i) for i in range(1,l+1))"
       ],
       "metadata": {
         "id": "Jd07MLgTiJ5H"
       },
-      "execution_count": 20,
+      "execution_count": 52,
       "outputs": []
     },
     {
       "cell_type": "code",
       "source": [
-        "RodCutting(p,5)"
+        "RodCutting(p,10)"
       ],
       "metadata": {
         "colab": {
-          "base_uri": "https://localhost:8080/",
-          "height": 322
+          "base_uri": "https://localhost:8080/"
         },
         "id": "wQuKkSy7j9TI",
-        "outputId": "5b6d7026-e6b4-4946-984f-7335fa9325df"
+        "outputId": "dbb7353d-c007-4ad7-87ce-892ff602ba2e"
       },
-      "execution_count": 21,
+      "execution_count": 53,
       "outputs": [
         {
-          "output_type": "error",
-          "ename": "RecursionError",
-          "evalue": "ignored",
-          "traceback": [
-            "\u001b[0;31m---------------------------------------------------------------------------\u001b[0m",
-            "\u001b[0;31mRecursionError\u001b[0m                            Traceback (most recent call last)",
-            "\u001b[0;32m<ipython-input-21-2d4e6ac37040>\u001b[0m in \u001b[0;36m<cell line: 1>\u001b[0;34m()\u001b[0m\n\u001b[0;32m----> 1\u001b[0;31m \u001b[0mRodCutting\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0mp\u001b[0m\u001b[0;34m,\u001b[0m\u001b[0;36m5\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0m",
-            "\u001b[0;32m<ipython-input-20-78fc1a0e3b6e>\u001b[0m in \u001b[0;36mRodCutting\u001b[0;34m(p, l)\u001b[0m\n\u001b[1;32m      3\u001b[0m     \u001b[0;32mreturn\u001b[0m \u001b[0;36m0\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[1;32m      4\u001b[0m   \u001b[0;32melse\u001b[0m\u001b[0;34m:\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0;32m----> 5\u001b[0;31m    \u001b[0;32mreturn\u001b[0m \u001b[0mmax\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0mp\u001b[0m\u001b[0;34m[\u001b[0m\u001b[0mi\u001b[0m\u001b[0;34m]\u001b[0m\u001b[0;34m+\u001b[0m\u001b[0mRodCutting\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0mp\u001b[0m\u001b[0;34m,\u001b[0m\u001b[0ml\u001b[0m\u001b[0;34m-\u001b[0m\u001b[0mi\u001b[0m\u001b[0;34m)\u001b[0m \u001b[0;32mfor\u001b[0m \u001b[0mi\u001b[0m \u001b[0;32min\u001b[0m \u001b[0mrange\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0ml\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0m",
-            "\u001b[0;32m<ipython-input-20-78fc1a0e3b6e>\u001b[0m in \u001b[0;36m<genexpr>\u001b[0;34m(.0)\u001b[0m\n\u001b[1;32m      3\u001b[0m     \u001b[0;32mreturn\u001b[0m \u001b[0;36m0\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[1;32m      4\u001b[0m   \u001b[0;32melse\u001b[0m\u001b[0;34m:\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0;32m----> 5\u001b[0;31m    \u001b[0;32mreturn\u001b[0m \u001b[0mmax\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0mp\u001b[0m\u001b[0;34m[\u001b[0m\u001b[0mi\u001b[0m\u001b[0;34m]\u001b[0m\u001b[0;34m+\u001b[0m\u001b[0mRodCutting\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0mp\u001b[0m\u001b[0;34m,\u001b[0m\u001b[0ml\u001b[0m\u001b[0;34m-\u001b[0m\u001b[0mi\u001b[0m\u001b[0;34m)\u001b[0m \u001b[0;32mfor\u001b[0m \u001b[0mi\u001b[0m \u001b[0;32min\u001b[0m \u001b[0mrange\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0ml\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0m",
-            "... last 2 frames repeated, from the frame below ...\n",
-            "\u001b[0;32m<ipython-input-20-78fc1a0e3b6e>\u001b[0m in \u001b[0;36mRodCutting\u001b[0;34m(p, l)\u001b[0m\n\u001b[1;32m      3\u001b[0m     \u001b[0;32mreturn\u001b[0m \u001b[0;36m0\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[1;32m      4\u001b[0m   \u001b[0;32melse\u001b[0m\u001b[0;34m:\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0;32m----> 5\u001b[0;31m    \u001b[0;32mreturn\u001b[0m \u001b[0mmax\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0mp\u001b[0m\u001b[0;34m[\u001b[0m\u001b[0mi\u001b[0m\u001b[0;34m]\u001b[0m\u001b[0;34m+\u001b[0m\u001b[0mRodCutting\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0mp\u001b[0m\u001b[0;34m,\u001b[0m\u001b[0ml\u001b[0m\u001b[0;34m-\u001b[0m\u001b[0mi\u001b[0m\u001b[0;34m)\u001b[0m \u001b[0;32mfor\u001b[0m \u001b[0mi\u001b[0m \u001b[0;32min\u001b[0m \u001b[0mrange\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0ml\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0m",
-            "\u001b[0;31mRecursionError\u001b[0m: maximum recursion depth exceeded"
-          ]
+          "output_type": "execute_result",
+          "data": {
+            "text/plain": [
+              "30"
+            ]
+          },
+          "metadata": {},
+          "execution_count": 53
         }
       ]
     },
     {
       "cell_type": "code",
-      "source": [],
+      "source": [
+        "r = [0]\n",
+        "\n",
+        "def RodCutMemo(p,r,l):\n",
+        "  if len(r)>l:\n",
+        "    return r[l]\n",
+        "  else:\n",
+        "    for j in range(len(r),l+1):\n",
+        "      r.append(max(p[i]+RodCutMemo(p,r,j-i) for i in range(1,j+1)))\n",
+        "    return r[l]"
+      ],
       "metadata": {
         "id": "CBCpbRrSkAc2"
       },
+      "execution_count": 101,
+      "outputs": []
+    },
+    {
+      "cell_type": "code",
+      "source": [
+        "RodCutMemo(p,r,5)"
+      ],
+      "metadata": {
+        "id": "rD8bMhVhuCxz",
+        "outputId": "9bb55847-f7bc-4c4b-e288-4b6123d3f757",
+        "colab": {
+          "base_uri": "https://localhost:8080/"
+        }
+      },
+      "execution_count": 102,
+      "outputs": [
+        {
+          "output_type": "execute_result",
+          "data": {
+            "text/plain": [
+              "13"
+            ]
+          },
+          "metadata": {},
+          "execution_count": 102
+        }
+      ]
+    },
+    {
+      "cell_type": "code",
+      "source": [
+        "r"
+      ],
+      "metadata": {
+        "id": "BxoHkCL4uGy8",
+        "outputId": "64d83c24-6952-4f4f-95ab-44835f851e2b",
+        "colab": {
+          "base_uri": "https://localhost:8080/"
+        }
+      },
+      "execution_count": 103,
+      "outputs": [
+        {
+          "output_type": "execute_result",
+          "data": {
+            "text/plain": [
+              "[0, 1, 5, 8, 10, 13]"
+            ]
+          },
+          "metadata": {},
+          "execution_count": 103
+        }
+      ]
+    },
+    {
+      "cell_type": "code",
+      "source": [],
+      "metadata": {
+        "id": "kGtsB8ifxllG"
+      },
       "execution_count": null,
       "outputs": []
     }