We asked this as a Java interview question and I HAD to show them the beauty of Python ;)

parentesis_checker.ipynb

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     "text": [
      "[{{{[{}{}{}]()}()}[{}{}{}]}]\n",
      "[{{{[]()}()}[]}]\n",
      "[{{{()}()}}]\n",
      "[{{{}}}]\n",
      "[{{}}]\n",
      "[{}]\n",
      "[]\n",
      "\n",
      "\n",
      "\n",
      "\n"
     ]
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   "source": [
    "import re\n",
    "\n",
    "# check this text for parenthesis error, neglect other chars\n",
    "text = '[{a{b{\\n[\\t{ü}^C{}{}]()}()}[\\t{ü}^C{}{}]}]'\n",
    "\n",
    "r = '[\\[\\{\\(\\)\\}\\]]'\n",
    "s = ''.join(re.findall(r, text))\n",
    "ps = ['[]', '()', '{}']\n",
    "\n",
    "for _ in range(int(len(s)/2)):\n",
    "    print(s)\n",
    "    s = min([s.replace(t,'') for t in ps], key=len)\n",
    "\n",
    "assert len(s) == 0, 'Could not break down ' + s"
   ]
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