#wire_2=(U62 R66 U55 R34 D71 R55 D58 R83)
# these wires should get 135
-wire_1=(R98 U47 R26 D63 R33 U87 L62 D20 R33 U53 R51)
-wire_2=(U98 R91 D20 R16 D67 R40 U7 R15 U6 R7)
+#wire_1=(R98 U47 R26 D63 R33 U87 L62 D20 R33 U53 R51)
+#wire_2=(U98 R91 D20 R16 D67 R40 U7 R15 U6 R7)
# read in data from file instead
-#exec 3<input.txt
-#IFS="," read -u 3 -a wire_1
-#IFS="," read -u 3 -a wire_2
-
-get_min_max() {
- local -n wire=$1
- horz_min=0
- horz_max=0
- vert_min=0
- vert_max=0
- cur_horz=0
- cur_vert=0
- for instruction in "${wire[@]}"; do
- direction=${instruction:0:1}
- amount=${instruction:1}
- case $direction in
- U)
- cur_vert=$((cur_vert+$amount))
- if [ $cur_vert -gt $vert_max ]; then
- vert_max=$cur_vert
- fi
- ;;
- D)
- cur_vert=$((cur_vert-$amount))
- if [ $cur_vert -lt $vert_min ]; then
- vert_min=$cur_vert
- fi
- ;;
- R)
- cur_horz=$((cur_horz+$amount))
- if [ $cur_horz -gt $horz_max ]; then
- horz_max=$cur_horz
- fi
- ;;
- L)
- cur_horz=$((cur_horz-$amount))
- if [ $cur_horz -lt $horz_min ]; then
- horz_min=$cur_horz
- fi
- ;;
- esac
- done
-
- echo "$horz_min,$horz_max,$vert_min,$vert_max"
-}
+exec 3<input.txt
+IFS="," read -u 3 -a wire_1
+IFS="," read -u 3 -a wire_2
trace_wire() {
local -n w=$1
local -n b=$2
local -n c=$3
- min_left=$4
+ wire_number=$4
cur_vert=0
cur_horz=0
moved=0
case $direction in
U|D)
- last_replace_char="|"
- offset=$((0-$min_left))
- offset=$((offset+$cur_horz))
for (( moved=1; moved <= $amount; moved++ )); do
cur_vert=$((cur_vert${operator}1))
- cur_line=${b[$cur_vert]}
- cur_char=${cur_line:$offset:1}
- replace_char="|"
- if [ $cur_char = "-" ] || [ $cur_char = "|" ]; then
- replace_char="X"
- c+=($cur_horz,$cur_vert)
- fi
- if [ $moved -eq $amount ]; then
- replace_char="+"
+ if [ ${b[$cur_horz,$cur_vert]+a} ] && [ $wire_number -eq 2 ]; then
+ if [ ${b[$cur_horz,$cur_vert]} -eq 1 ]; then
+ c+=($cur_horz,$cur_vert)
+ b[$cur_horz,$cur_vert]=3
+ fi
+ continue
fi
- if [ $cur_vert -eq 0 ] && [ $cur_horz -eq 0 ]; then
- replace_char='o'
- fi
- new_line="${cur_line:0:$((offset))}${replace_char}${cur_line:$((offset+1))}"
- b[$cur_vert]=$new_line
+ b[$cur_horz,$cur_vert]=$wire_number
done
;;
L|R)
- last_replace_char="-"
- # this could change multiple characters in the line
for (( moved=1; moved <= $amount; moved++ )); do
cur_horz=$((cur_horz${operator}1))
- offset=$((0-$min_left))
- offset=$((offset+$cur_horz))
- cur_line=${b[$cur_vert]}
- cur_char=${cur_line:$offset:1}
- replace_char="-"
- if [ $cur_char = "-" ] || [ $cur_char = "|" ]; then
- replace_char="X"
- c+=($cur_horz,$cur_vert)
- fi
- if [ $moved -eq $amount ]; then
- replace_char="+"
- fi
- if [ $cur_vert -eq 0 ] && [ $cur_horz -eq 0 ]; then
- replace_char='o'
+ if [ ${b[$cur_horz,$cur_vert]+a} ] && [ $wire_number -eq 2 ]; then
+ if [ ${b[$cur_horz,$cur_vert]} -eq 1 ]; then
+ c+=($cur_horz,$cur_vert)
+ b[$cur_horz,$cur_vert]=3
+ fi
+ continue
fi
- new_line="${cur_line:0:$((offset))}${replace_char}${cur_line:$((offset+1))}"
- b[$cur_vert]=$new_line
+ b[$cur_horz,$cur_vert]=$wire_number
done
;;
esac
done
-
- cur_line=${b[$cur_vert]}
- offset=$((0-$min_left))
- offset=$((offset+$cur_horz))
- if [ ${cur_line:$offset:1} != 'X' ]; then
- new_line="${cur_line:0:$((offset))}${last_replace_char}${cur_line:$((offset+1))}"
- b[$cur_vert]=$new_line
- fi
- echo
}
-make_board() {
- local -n mm=$1
- local -n b=$2
-
- min_horz=${mm[0]}
- if [ $min_horz -gt 0 ]; then
- min_horz=0
- fi
-
- min_vert=${mm[2]}
- if [ $min_vert -gt 0 ]; then
- min_vert=0
- fi
-
- max_horz=${mm[1]}
- total_horz=$(($max_horz - $min_horz))
-
- max_vert=${mm[3]}
-
- cur_vert=${min_vert}
- blank_string=$(printf ".%.0s" $(eval echo '{0..'$total_horz'}'))
- while [[ $cur_vert -le ${max_vert} ]]; do
- if [[ $cur_vert -eq 0 ]]; then
- offset=$((0-${mm[0]}))
- line="${blank_string:0:$offset}o${blank_string:$((offset+1))}"
- b[$cur_vert]=$line
- else
- b[$cur_vert]=$blank_string
- fi
- cur_vert=$((cur_vert+1))
- done
-}
-
-echo "Getting board boundaries"
-IFS="," read -a min_max < <(get_min_max wire_1)
-IFS="," read -a min_max_2 < <(get_min_max wire_2)
-
-# do the minimums first
-for pos in 0 2; do
- if [ ${min_max[$pos]} -gt ${min_max_2[$pos]} ]; then
- min_max[$pos]=${min_max_2[$pos]}
- fi
-done
-
-# now the maximums
-for pos in 1 3; do
- if [ ${min_max[$pos]} -lt ${min_max_2[$pos]} ]; then
- min_max[$pos]=${min_max_2[$pos]}
- fi
-done
-
-echo " ${min_max[@]}"
-
-# we now know exactly how big the grid is, which is handy, as we'll use it to do offsets
declare -A board
declare -a cross_wires
-echo "Building board"
-make_board min_max board
echo "Tracing first wire"
-trace_wire wire_1 board cross_wires ${min_max[0]}
+trace_wire wire_1 board cross_wires 1
echo "Tracing second wire"
-trace_wire wire_2 board cross_wires ${min_max[0]}
-
-for (( a=${min_max[3]}; a>=${min_max[2]}; a-- )); do
- echo ${board[$a]}
-done
+trace_wire wire_2 board cross_wires 2
echo "Wires cross at:"
min_distance=-1
projects / advent-of-code-2019.git / blobdiff