day 43 - shuffle.ipynb

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   "source": [
    "import numpy as np"
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   "source": [
    "## algorithm"
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    "def shuffle(data):\n",
    "    n = len(data)\n",
    "    for i in range(n):\n",
    "        k = np.random.randint(i, n)\n",
    "        data[i], data[k] = data[k], data[i]\n",
    "        \n",
    "    return data"
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   "source": [
    "## shuffle"
   ]
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   "source": [
    "data = list(range(10))"
   ]
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    "shuffle(data)"
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    "shuffle(data)"
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    "shuffle(data)"
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