{
 "cells": [
  {
   "cell_type": "code",
   "id": "initial_id",
   "metadata": {
    "collapsed": true,
    "ExecuteTime": {
     "end_time": "2026-01-28T04:26:42.103401300Z",
     "start_time": "2026-01-28T04:26:42.066578300Z"
    }
   },
   "source": [
    "arr = [1, 2, 3, 4, 5]\n",
    "a = 1\n",
    "b = 3\n",
    "b_index = arr.index(b)\n",
    "arr.remove(a)\n",
    "arr.insert(b_index - 1, a)\n",
    "print(arr)"
   ],
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "[2, 1, 3, 4, 5]\n"
     ]
    }
   ],
   "execution_count": 2
  }
 ],
 "metadata": {
  "kernelspec": {
   "display_name": "Python 3",
   "language": "python",
   "name": "python3"
  },
  "language_info": {
   "codemirror_mode": {
    "name": "ipython",
    "version": 2
   },
   "file_extension": ".py",
   "mimetype": "text/x-python",
   "name": "python",
   "nbconvert_exporter": "python",
   "pygments_lexer": "ipython2",
   "version": "2.7.6"
  }
 },
 "nbformat": 4,
 "nbformat_minor": 5
}