gistfile1.txt

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 "metadata": {
  "name": "",
  "signature": "sha256:767a7d71da34f21ef483ff6e9864b38cdeb9361d1e0edf037f79f8a4df0138e2"
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 "worksheets": [
  {
   "cells": [
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "def my_foldl(f, x0, lst):\n",
      "    for x in lst:\n",
      "        x0 = f(x0, x)\n",
      "    return x0\n",
      "\n",
      "def my_foldr(f, x0, lst):\n",
      "    for x in lst[::-1]:\n",
      "        x0 = f(x0, x)\n",
      "    return x0\n",
      "\n",
      "def concat(a, b):\n",
      "    return a + b"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [],
     "prompt_number": 1
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "def my_foldl2(f, x0, lst):\n",
      "    \"\"\"\u0424\u0443\u043d\u043a\u0446\u0438\u044f, \u0440\u0435\u0430\u043b\u0438\u0437\u0443\u044e\u0449\u0430\u044f \u0441\u0432\u0451\u0440\u0442\u043a\u0443 \u0441\u043b\u0435\u0432\u0430, \u0438\u0441\u043f\u043e\u043b\u044c\u0437\u0443\u044f \u0441\u0432\u0451\u0440\u0442\u043a\u0443 \u0441\u043f\u0440\u0430\u0432\u0430.\"\"\"\n",
      "    return (my_foldr(lambda a, b: lambda x: a(f(x, b)), lambda x:x, lst)(x0))"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [],
     "prompt_number": 14
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "print(my_foldl2(concat, 'a', ['b', 'c']))\n",
      "print(my_foldl(concat, 'a', ['b', 'c']))\n",
      "print(my_foldr(concat, 'a', ['b', 'c']))"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "abc\n",
        "abc\n",
        "acb\n"
       ]
      }
     ],
     "prompt_number": 17
    }
   ],
   "metadata": {}
  }
 ]
}