Still not working, but stuff removed that was wrong.

src/aoc2025/Day10.kt

@@ -128,42 +128,23 @@ fun main() {
                 v.min = minT
             }
 
-            // look at which different possible sets of toggles need to be pressed to result in the target number
-            // pressing an even time will cancel out the effect, so only look what happens if you press once
-            val oddset = ArrayList<Set<Toggle>>()
-            for (tm in 1 until (1 shl toggles.size)) {
-                val odds = toggles.withIndex().filter { (i, _) -> (1 shl i) and tm != 0 }.map { it.value }.toSet()
-                val result = odds.fold(0) { acc, iv -> acc xor iv.v }
-                if (result == m.target) {
-                    oddset.add(odds)
-                }
-            }
-
             // iterate over the possible odd sets
             var minPushes = Int.MAX_VALUE
-            newodd@ for (odds in oddset) {
             val jolts = m.joltage.copyOf()
             val pressCount = IntArray(m.toggles.size)
 
             // press all buttons regarding their minimal count (if any)
             for (t in toggles) {
-                    if (pressCount[t.idx] + t.min > t.max || !applyJoltage(jolts, t, times = t.min)) continue@newodd
+                if (pressCount[t.idx] + t.min > t.max || !applyJoltage(
+                        jolts,
+                        t,
+                        times = t.min
+                    )
+                ) throw IllegalStateException()
                 pressCount[t.idx] += t.min
-
-                    if (odds.contains(t)) {
-                        // make sure that the buttons that will lead to a solution have an odd count
-                        if (pressCount[t.idx] and 1 == 0) {
-                            if (++pressCount[t.idx] > t.max || !applyJoltage(jolts, t)) continue@newodd
-                        }
-                    } else {
-                        // make sure that the buttons that will destroy the solution have an even count
-                        if (pressCount[t.idx] and 1 == 1) {
-                            if (++pressCount[t.idx] > t.max || !applyJoltage(jolts, t)) continue@newodd
-                        }
-                    }
             }
             // this is the starting point for the exhaustive search
-                val pq = LinkedList<Pair<IntArray, IntArray>>()
+            val pq = PriorityQueue(compareBy<Pair<IntArray, IntArray>> { it.second.sum() })
             pq.add(jolts to pressCount)
             while (pq.isNotEmpty()) {
                 val (j, tc) = pq.poll()
@@ -188,7 +169,6 @@ fun main() {
                     }
                 }
             }
-            }
             println("$minPushes")
             sumButts += minPushes
         }