Project Euler Q29 - LO Man Hei

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    "### Q29\n",
    "How many distinct terms are in the sequence generated by \\( a^{b} \\) for \\( 2 \\le a \\le 100 \\) and \\( 2 \\le b \\le 100 \\)?"
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    "def int_log(n,base):\n",
    "    result = 0\n",
    "    while int(n) >= base:\n",
    "        n /= base\n",
    "        result += 1\n",
    "    return result\n",
    "\n",
    "def distinct_a_pow_b(a_lims,b_lims):\n",
    "    reduce_map = dict()\n",
    "    reduce_map_a_lim = a_lims[1]**0.5\n",
    "    reduce_map_b_lim = int_log(a_lims[1],2)\n",
    "    distinct_set = set()\n",
    "    for a in range(a_lims[0],a_lims[1]+1):\n",
    "        for b in range(b_lims[0],b_lims[1]+1):\n",
    "            temp_set = (reduce_map[a][0],reduce_map[a][1]*b) if a in reduce_map else (a,b)\n",
    "            if 1 < a <= reduce_map_a_lim and b <= reduce_map_b_lim and temp_set[0]**temp_set[1] <= a_lims[1]:\n",
    "                reduce_map[a**b] = temp_set\n",
    "            distinct_set.add(temp_set)\n",
    "    return len(distinct_set)"
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     "text": [
      "CPU times: user 1.89 ms, sys: 472 µs, total: 2.36 ms\n",
      "Wall time: 2.36 ms\n"
     ]
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       "9183"
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   "source": [
    "%%time\n",
    "distinct_a_pow_b([2,100],[2,100])"
   ]
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   "execution_count": 3,
   "id": "1948584e-48e5-4835-8fad-bdc4865cac2d",
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     "text": [
      "CPU times: user 5.13 ms, sys: 0 ns, total: 5.13 ms\n",
      "Wall time: 4.93 ms\n"
     ]
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       "9183"
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     "execution_count": 3,
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   "source": [
    "%%time\n",
    "len(list(set(i**j for i in range(2,101) for j in range(2,101))))"
   ]
  },
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   "execution_count": null,
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