CADDi 2018 for Beginners C - Product and GCD code.ipynb

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   "execution_count": 13,
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     "name": "stdout",
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     "text": [
      "stdin> 4 972439611840\n"
     ]
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     "data": {
      "text/plain": [
       "2-element Array{Int64,1}:\n",
       "            4\n",
       " 972439611840"
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     "execution_count": 13,
     "metadata": {},
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   "source": [
    "N, P = map(x -> parse(Int64, x), split(readline(STDIN)))"
   ]
  },
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   "cell_type": "code",
   "execution_count": 14,
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     "data": {
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       "4"
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     "execution_count": 14,
     "metadata": {},
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   "source": [
    "N"
   ]
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  {
   "cell_type": "code",
   "execution_count": 15,
   "metadata": {},
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     "data": {
      "text/plain": [
       "972439611840"
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     "execution_count": 15,
     "metadata": {},
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   "source": [
    "P"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 4,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "primes (generic function with 1 method)"
      ]
     },
     "execution_count": 4,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "function primes(n)\n",
    "    prime_factors = Dict{Int64, Int64}()\n",
    "    divisor = 2\n",
    "    \n",
    "    while divisor ^ 2 <= n\n",
    "        count = 0\n",
    "        while n % divisor == 0\n",
    "            count += 1\n",
    "            n ÷= divisor\n",
    "        end\n",
    "        if count > 0\n",
    "            prime_factors[divisor] = count\n",
    "        end\n",
    "        divisor += 1\n",
    "    end\n",
    "    \n",
    "    if n > 1\n",
    "        prime_factors[n] = 1\n",
    "    end\n",
    "    \n",
    "    return prime_factors\n",
    "end"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 5,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "Dict{Int64,Int64} with 2 entries:\n",
       "  2 => 1\n",
       "  5 => 1"
      ]
     },
     "execution_count": 5,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "primes(10)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 6,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "Dict{Int64,Int64} with 2 entries:\n",
       "  2 => 2\n",
       "  5 => 1"
      ]
     },
     "execution_count": 6,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "primes(20)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 16,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "Dict{Int64,Int64} with 4 entries:\n",
       "  2   => 6\n",
       "  3   => 3\n",
       "  103 => 4\n",
       "  5   => 1"
      ]
     },
     "execution_count": 16,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "primes_dic = primes(P)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 8,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "cal_k (generic function with 1 method)"
      ]
     },
     "execution_count": 8,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "cal_k(pair) = pair.first ^ floor(Int64, pair.second / N)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 9,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "2"
      ]
     },
     "execution_count": 9,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "mapreduce(x-> cal_k(x), *, primes_dic)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 10,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "2-element Array{Int64,1}:\n",
       " 2\n",
       " 1"
      ]
     },
     "execution_count": 10,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "[cal_k(pair) for pair in primes_dic]"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 17,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "206"
      ]
     },
     "execution_count": 17,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "answer = length(primes_dic) == 0 ? 1 : mapreduce(x-> cal_k(x), *, primes_dic)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 18,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "206\n"
     ]
    }
   ],
   "source": [
    "println(answer)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": []
  }
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