Project Euler Q18 - LO Man Hei

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   "source": [
    "### Q18\n",
    "Find the maximum total from top to bottom of the triangle below:"
   ]
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    "num_triangle_string = \"\"\"\n",
    "75\n",
    "95 64\n",
    "17 47 82\n",
    "18 35 87 10\n",
    "20 04 82 47 65\n",
    "19 01 23 75 03 34\n",
    "88 02 77 73 07 63 67\n",
    "99 65 04 28 06 16 70 92\n",
    "41 41 26 56 83 40 80 70 33\n",
    "41 48 72 33 47 32 37 16 94 29\n",
    "53 71 44 65 25 43 91 52 97 51 14\n",
    "70 11 33 28 77 73 17 78 39 68 17 57\n",
    "91 71 52 38 17 14 91 43 58 50 27 29 48\n",
    "63 66 04 68 89 53 67 30 73 16 69 87 40 31\n",
    "04 62 98 27 23 09 70 98 73 93 38 53 60 04 23\n",
    "\"\"\""
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   "source": [
    "def num_triangle_string_to_list(num_triangle_string):\n",
    "    return [[int(ele) for ele in line.strip().split(\" \")] for line in num_triangle_string.strip().split(\"\\n\")]\n",
    "\n",
    "def vector_add(vector_a,vector_b):\n",
    "    return [vector_a[i]+vector_b[i] for i in range(len(vector_a))]\n",
    "\n",
    "def max_path(num_triangle_string):\n",
    "    num_triangle_list = num_triangle_string_to_list(num_triangle_string)\n",
    "    num_list_len = len(num_triangle_list)\n",
    "    if num_list_len == 0:\n",
    "        return 0\n",
    "    if num_list_len == 1:\n",
    "        return num_triangle_list[0][0]\n",
    "    for i in range(num_list_len-2,-1,-1):\n",
    "        sons = num_triangle_list.pop()\n",
    "        max_sons = [sons[j] if sons[j] > sons[j+1] else sons[j+1] for j in range(i+1)]\n",
    "        num_triangle_list[i] = vector_add(num_triangle_list[i],max_sons)\n",
    "    return num_triangle_list[0][0]"
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    {
     "name": "stdout",
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     "text": [
      "CPU times: user 35 µs, sys: 5 µs, total: 40 µs\n",
      "Wall time: 40.8 µs\n"
     ]
    },
    {
     "data": {
      "text/plain": [
       "1074"
      ]
     },
     "execution_count": 3,
     "metadata": {},
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   ],
   "source": [
    "%%time\n",
    "max_path(num_triangle_string)"
   ]
  },
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   "execution_count": null,
   "id": "b7d67ff3-af1d-4b43-b5e1-321c0b0440b7",
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   "source": []
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