75 lines
1.6 KiB
Plaintext
75 lines
1.6 KiB
Plaintext
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{
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"cells": [
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{
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"cell_type": "markdown",
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"id": "d5ba1893",
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"metadata": {},
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"source": [
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"# [Pandigital Multiples](https://projecteuler.net/problem=38)\n",
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"\n",
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"Any number with five or more digits will have a concatenated product with more than 9 digits. Therefore we only need to check numbers with less than five digits."
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]
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},
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{
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"cell_type": "code",
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"execution_count": 1,
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"id": "ffea7112",
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"metadata": {},
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"outputs": [
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{
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"data": {
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"text/plain": [
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"932718654"
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]
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},
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"execution_count": 1,
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"metadata": {},
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"output_type": "execute_result"
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}
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],
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"source": [
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"from itertools import count\n",
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"\n",
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"def is_pandigital(s):\n",
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" return ''.join(sorted(s)) == \"123456789\"\n",
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"\n",
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"\n",
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"pandigitals = set()\n",
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"for k in range(1, 10000):\n",
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" s = \"\"\n",
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" for n in count(1):\n",
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" s += str(k * n)\n",
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" if len(s) >= 9:\n",
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" break\n",
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" \n",
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" if is_pandigital(s):\n",
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" pandigitals.add(int(s))\n",
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"\n",
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" \n",
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"max(pandigitals)"
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]
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}
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],
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"metadata": {
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"kernelspec": {
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"display_name": "SageMath 9.5",
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"language": "sage",
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"name": "sagemath"
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},
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"language_info": {
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"codemirror_mode": {
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"name": "ipython",
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"version": 3
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},
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"file_extension": ".py",
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"mimetype": "text/x-python",
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"name": "python",
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"nbconvert_exporter": "python",
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"pygments_lexer": "ipython3",
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"version": "3.11.2"
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}
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},
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"nbformat": 4,
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"nbformat_minor": 5
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}
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