#!/usr/bin/env bash

FILE=input
read -r -a INPUT_ARRAY <<< "$( sed -E 's/.*X[\+\=]([0-9]+), Y[\+\=]([0-9]+)/\1 \2 /g' < "$FILE" | paste -s -d " " )"
printf "%s\n" "${INPUT_ARRAY[@]}" >&2
INPUT_LEN=${#INPUT_ARRAY[@]}

TOTAL_TOKEN=0
for (( i=0 ; i < INPUT_LEN; i+=6 ))
do
  A=${INPUT_ARRAY[i]}
  C=${INPUT_ARRAY[i+1]}
  B=${INPUT_ARRAY[i+2]}
  D=${INPUT_ARRAY[i+3]}
  X="10000000000000${INPUT_ARRAY[i+4]}"
  Y="10000000000000${INPUT_ARRAY[i+5]}"

  I=$(( ( B*Y - D*X ) / ( B*C - D*A ) )) # Button A
  J=$(( ( X - A*I ) / B )) # Button B

  TOKEN=$(( I*3 + J*1 ))

  {
    printf "Answer: I= %s, J= %s\n" "$I" "$J"
    printf "Verify answer : %s to %s, %s to %s\n" "$(( A*I + B*J ))" "$X" "$(( C*I + D*J ))" "$Y"
    printf "Total cost: %s\n" "$(( I*3 + J*1 ))"
  } >&2

  if ! [[ $(( A*I + B*J )) -eq $X ]]
  then
    continue
  elif ! [[ $(( C*I + D*J )) -eq $Y ]]
  then
    continue
  elif [[ $I -lt 1 ]] || [[ $J -lt 1 ]]
  then
    continue
  #elif [[ $I -gt 100 ]] || [[ $J -gt 100 ]]
  #then
  #  continue
  else
    (( TOTAL_TOKEN+=TOKEN ))
  fi
done
printf "Total token: %s\n" "$TOTAL_TOKEN"