Project Euler Q26 - LO Man Hei

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   "source": [
    "### Q26\n",
    "Find the value of d < 1000 for which \\( \\frac{1}{d} \\) contains the longest recurring cycle in its decimal fraction part."
   ]
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    "def recurring_len(n):\n",
    "    if int('9'*(n-1))%n != 0:\n",
    "        return 0\n",
    "    else:\n",
    "        recurring_nums = str(int('9'*(n-1))//n)\n",
    "        return (n-1)//recurring_nums.count(recurring_nums[:len(str(n))+1])\n",
    "\n",
    "def longest_recurring_cycle(max_range):\n",
    "    for n in range(1,max_range)[::-1]:\n",
    "        if recurring_len(n) == n-1:\n",
    "            return n\n",
    "                "
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     "text": [
      "CPU times: user 130 µs, sys: 37 µs, total: 167 µs\n",
      "Wall time: 169 µs\n"
     ]
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   "source": [
    "%%time\n",
    "longest_recurring_cycle(1000)"
   ]
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   "id": "bb16c22a-fd2e-47a5-9815-293e6f84569a",
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   "source": []
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