python3/0069_sqrtx.ipynb

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    "class Solution:\n",
    "    #二分法\n",
    "    def mySqrt(self, x):\n",
    "        \"\"\"\n",
    "        :type x: int\n",
    "        :rtype: int\n",
    "        \"\"\"\n",
    "        if x < 2:\n",
    "            return x\n",
    "        half = x // 2\n",
    "        up = x\n",
    "        down = 0\n",
    "        while (up - down) > 1:\n",
    "            hsqrt = half ** 2\n",
    "            print(hsqrt)\n",
    "            if hsqrt > x:\n",
    "                up = half\n",
    "            elif hsqrt < x:\n",
    "                down = half\n",
    "            else:\n",
    "                break\n",
    "            half = (up   down) //2\n",
    "        return half\n",
    "    #简略版\n",
    "    def mySqrt1(self, x):\n",
    "        \"\"\"\n",
    "        :type x: int\n",
    "        :rtype: int\n",
    "        \"\"\"\n",
    "        r = x\n",
    "        while r * r > x:\n",
    "            r = (r   x // r) // 2\n",
    "        return r"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 70,
   "metadata": {},
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     "execution_count": 70,
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   "source": [
    "Solution().mySqrt(1)"
   ]
  },
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   "execution_count": 64,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "2.8284271247461903"
      ]
     },
     "execution_count": 64,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "import math\n",
    "math.sqrt(8)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": []
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