day02/sub.sh

   1 #!/bin/bash
   2
   3 exec 3<input.txt
   4 depth=0
   5 horizontal=0
   6 aim=0
   7 aim_depth=0
   8 aim_horizontal=0
   9
  10 while read -a things -u 3; do
  11     case ${things[0]} in
  12         up)
  13             ((depth-=${things[1]}))
  14             ((aim-=${things[1]}))
  15             ;;
  16         down)
  17             ((depth+=${things[1]}))
  18             ((aim+=${things[1]}))
  19             ;;
  20         forward)
  21             ((horizontal+=${things[1]}))
  22             depth_calc=$((things[1]*aim))
  23             ((aim_depth+=$depth_calc))
  24             ((aim_horizontal+=${things[1]}))
  25             ;;
  26     esac
  27 done
  28
  29 echo "horz * depth = $((depth*$horizontal))"
  30 echo "aimed version = $((aim_depth*$aim_horizontal))"