Project Euler Q67 - LO Man Hei

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   "source": [
    "### Q67\n",
    "Find the maximum total from top to bottom in [file](/notebook/raw/q67_data.txt), a 15K text file containing a triangle with one-hundred rows."
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    "num_triangle_string = open(\"q67_data.txt\",\"r\").read()"
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    "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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     "text": [
      "CPU times: user 837 µs, sys: 136 µs, total: 973 µs\n",
      "Wall time: 975 µs\n"
     ]
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       "7273"
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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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