Project Euler Q24 - LO Man Hei

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   "source": [
    "### Q24\n",
    "What is the millionth lexicographic permutation of the digits 0, 1, 2, 3, 4, 5, 6, 7, 8 and 9?"
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    "def factorial(n):\n",
    "    return n*factorial(n-1) if n > 1 else 1\n",
    "    \n",
    "def n_lexicographic_permutation(n,shift_n=-1):\n",
    "    n += shift_n\n",
    "    digit_weighting = {i:factorial(i) for i in range(10)}\n",
    "    remaining_digit = list(range(10))\n",
    "    digit_list = []\n",
    "    for i in range(10)[::-1]:\n",
    "        coeff = n // digit_weighting[i]\n",
    "        n -= digit_weighting[i] * coeff\n",
    "        digit_list.append(remaining_digit.pop(coeff))\n",
    "    return \"\".join(str(i) for i in digit_list)"
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      "CPU times: user 15 µs, sys: 3 µs, total: 18 µs\n",
      "Wall time: 19.6 µs\n"
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   "source": [
    "%%time\n",
    "n_lexicographic_permutation(1000000)"
   ]
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