Project Euler Q36 - LO Man Hei

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   "source": [
    "### Q36\n",
    "Find the sum of all numbers, less than one million, which are palindromic in base 10 and base 2."
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    "def palindromic_creator(n):\n",
    "    str_n = str(n)\n",
    "    return [int(str_n+str_n[::-1]),int(str_n[:-1]+str_n[::-1])]\n",
    "\n",
    "def dec_to_bin(dec):\n",
    "    return bin(dec).replace(\"0b\", \"\")\n",
    "\n",
    "def is_palindromic_base2(dec):\n",
    "    str_base2 = dec_to_bin(dec)\n",
    "    return str_base2 == str_base2[::-1]\n",
    "\n",
    "def palindromic_base2_and_base10(n):\n",
    "    half_range = int(str(n)[0]) * 10 ** ((len(str(n))+1)//2)\n",
    "    result = set()\n",
    "    for i in range(1,half_range):\n",
    "        for palindromic_base10 in palindromic_creator(i):\n",
    "            if is_palindromic_base2(palindromic_base10):\n",
    "                result.add(palindromic_base10)\n",
    "    return result"
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      "CPU times: user 9.51 ms, sys: 0 ns, total: 9.51 ms\n",
      "Wall time: 8.77 ms\n"
     ]
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       "39347399"
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   "source": [
    "%%time\n",
    "sum(palindromic_base2_and_base10(1000000))"
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   "source": [
    "def palindromic_base2_and_base10_2(n):\n",
    "    base10_half_range = int(str(n)[0]) * 10 ** ((len(str(n))+1)//2)\n",
    "    palindromic_base10 = { i for n in range(base10_half_range) for i in palindromic_creator(n) }\n",
    "    palindromic_base2 = { int(str(i),base=2) for n in range(base10_half_range) for i in palindromic_creator(dec_to_bin(n)) }\n",
    "    return palindromic_base10.intersection(palindromic_base2)"
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     "text": [
      "CPU times: user 27.2 ms, sys: 243 µs, total: 27.5 ms\n",
      "Wall time: 25.4 ms\n"
     ]
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       "39347399"
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     "execution_count": 4,
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   "source": [
    "%%time\n",
    "sum(palindromic_base2_and_base10_2(1000000))"
   ]
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