day14/calc_fuel.sh

   1 #!/bin/bash
   2
   3 basedir=$(dirname $(readlink -f ${BASH_SOURCE}))
   4 filename="${1:-31_ORE_1_FUEL.txt}"
   5
   6 declare -A chemicals
   7 declare -A requires
   8
   9 parse_line() {
  10     local line="$1"
  11     local p=${line#* => }
  12     local r=${line% =>*}
  13     local p_count
  14     local part
  15     local count
  16     local chem
  17     local -A dict
  18     local string
  19
  20     p_count=${p% *}
  21     p=${p#* }
  22     r=${r//, /|}
  23
  24     while [ ${#r} -gt 0 ]; do
  25         part=${r%%|*}
  26         count=${part% *}
  27         chem=${part#* }
  28         r=${r#$part}
  29         r=${r#|}
  30
  31         string+=" [$chem]=$count "
  32     done
  33     requires[${p}_${count}]="$string"
  34     if [ ${chemicals[$p]} ]; then
  35         chemicals[$p]+=" $count"
  36     else
  37         chemicals[$p]="$p_count"
  38     fi
  39 }
  40
  41 read_file() {
  42     exec 3<"$filename"
  43     local IFS=$'\n'
  44     while read -u 3 line; do
  45         parse_line "$line"
  46     done
  47 }
  48
  49 read_file
  50
  51 for key in ${!requires[@]}; do
  52     echo "$key -> ${requires[$key]}"
  53 done
  54
  55 echo
  56
  57 for key in ${!chemicals[@]}; do
  58     echo "$key -> ${chemicals[$key]}"
  59 done
  60
  61 declare -A needed
  62 needed=( "${requires[FUEL_1]}" )
  63
  64 for key in ${!needed[@]}; do
  65     echo "$key ${needed[$key]}"
  66 done