#!/bin/bash

scores=()
while read line; do
  chars=( $(sed 's/\(.\)/\1 /g' <<< $line) )
  opened_chars=()
  broken=0
  for char in ${chars[@]}; do
    case $char in
      '('|'['|'{'|'<')
        opened_chars+=( $char );;
      ')')
	if [ ${opened_chars[-1]} = '(' ]; then
	  unset 'opened_chars[-1]'
	else
	  broken=1
	  break
	fi;;
      ']')
	if [ ${opened_chars[-1]} = '[' ]; then
	  unset 'opened_chars[-1]'
	else
	  broken=1
	  break
	fi;;
      '}')
	if [ ${opened_chars[-1]} = '{' ]; then
	  unset 'opened_chars[-1]'
	else
	  broken=1
	  break
	fi;;
      '>')
	if [ ${opened_chars[-1]} = '<' ]; then
	  unset 'opened_chars[-1]'
	else
	  broken=1
	  break
	fi;;
    esac
  done
  if [ $broken -eq 0 ]; then
    score=0
    n_opened_chars=${#opened_chars[@]}
    for i in $(seq $((n_opened_chars-1)) -1 0); do
      case ${opened_chars[$i]} in
        '(')
          score=$((score*5+1));;
        '[')
          score=$((score*5+2));;
        '{')
          score=$((score*5+3));;
        '<')
          score=$((score*5+4));;
      esac
    done
    scores+=( $score )
  fi
done
scores=( $(printf '%s\n' "${scores[@]}" | sort -nr) )
n_scores=${#scores[@]}
echo ${scores[$((n_scores/2))]}