diff --git a/src/main/kotlin/Day03.kt b/src/main/kotlin/Day03.kt
new file mode 100644
index 0000000..9f36bc1
--- /dev/null
+++ b/src/main/kotlin/Day03.kt
@@ -0,0 +1,33 @@
+import utils.AoCDay
+import utils.splitAndMapToInt
+
+class Day03 : AoCDay() {
+
+    private val mulRegEx = """mul\(\d*,\d*\)""".toRegex()
+    private val inactiveRegex = """don't\(\).*?do\(\)""".toRegex()
+    private val code = input.joinToString("")
+    override fun part1(): Any {
+        val matches = mulRegEx.findAll(code)
+        var result = 0L
+        matches.forEach { match ->
+            val numbers = match.value.drop(4).dropLast(1).splitAndMapToInt(",")
+            result += numbers[0] * numbers[1]
+        }
+        return result
+    }
+
+    override fun part2(): Any {
+        var activeCode = code.replace(inactiveRegex, "")
+        val matches = mulRegEx.findAll(activeCode)
+        var result = 0L
+        matches.forEach { match ->
+            val numbers = match.value.drop(4).dropLast(1).splitAndMapToInt(",")
+            result += numbers[0] * numbers[1]
+        }
+        return result
+    }
+}
+
+fun main() {
+    Day03().execute()
+}