remove special-case initial loop nonsense

03/main.go

@@ -59,26 +59,18 @@ func partOne() {
 func partTwo() {
 	scanner := makeScanner(false)
 
-	var lines int
-	inputs := map[int]int64{}
+	inputs := []int64{}
 	var oxgen, co2scrub int64
 
-	var totalOnes, bitlen int64
+	var bitlen int64
 	for scanner.Scan() {
 		line := scanner.Text()
 		n, _ := strconv.ParseInt(line, 2, 64)
-		inputs[lines] = n
-		bitlen = int64(len(line)) - 1
-		totalOnes += n >> (bitlen)
-		lines++
-	}
-	// make initial check
-	if totalOnes >= int64(lines)/2 {
-		oxgen += (1 << bitlen)
-	} else {
-		co2scrub += (1 << bitlen)
+		inputs = append(inputs, n)
+		bitlen = int64(len(line))
 	}
 
+	// on initial loop, oxgen>>i == n>>i etc always come out to 0 == 0
 	for i := bitlen; i > 0; i-- {
 		var oxOnes, oxZeroes, coOnes, coZeroes int64
 		for _, n := range inputs {