Day 3 part 2

day-3/script.sh

@@ -10,4 +10,23 @@ while read line; do
         acc=$(expr $n1 \* $n2 + $acc)
     fi
 done <<< $(grep -Eo $regex input.txt)
-echo $acc
+echo "Part 1: $acc"
+
+# Part 2
+regex="(mul\(([0-9]{1,3}),([0-9]{0,3})\)|do\(\)|don't\(\))"
+acc=0
+enabled=1
+while read line; do
+    if [[ $line =~ $regex ]] then
+        if [[ $line == "do()" ]] then
+            enabled=1
+        elif [[ $line == "don't()" ]] then
+            enabled=0
+        else
+            n1=${BASH_REMATCH[2]}
+            n2=${BASH_REMATCH[3]}
+            [ $enabled -eq 1 ] && acc=$(expr $n1 \* $n2 + $acc)
+        fi
+    fi
+done <<< $(grep -Eo $regex input.txt)
+echo "Part 2: $acc"