feat: solve day 3 part 1

cmd/03/bank/bank.go

@@ -0,0 +1,102 @@
+// Package bank represents a bank of batteries
+package bank
+
+import (
+	"fmt"
+	"strconv"
+)
+
+type Bank interface {
+	Joltage() int
+	Cells() []int
+}
+
+type bank struct {
+	cells []int
+}
+
+func From(line string) Bank {
+	cells := []int{}
+
+	for _, char := range line {
+		num, _ := strconv.Atoi(string(char))
+		cells = append(cells, num)
+	}
+
+	return bank{
+		cells: cells,
+	}
+}
+
+type cell struct {
+	index int
+	value int
+}
+
+func (b bank) Joltage() int {
+	// TODO: We still need to
+	// find the max
+	// however we should then
+	// find the next max to the
+	// left of the highest
+	// and find the next max to
+	// the right of the higest
+	// we should then see what
+	// the large number we can make
+	// with these values
+
+	max := cell{
+		value: -1,
+	}
+
+	for ci, cv := range b.cells {
+		if cv > max.value {
+			max = cell{
+				index: ci,
+				value: cv,
+			}
+		}
+	}
+
+	maxLeft := cell{
+		value: -1,
+	}
+
+	for ci, cv := range b.cells[:max.index] {
+		if cv > maxLeft.value {
+			maxLeft = cell{
+				index: ci,
+				value: cv,
+			}
+		}
+	}
+
+	maxRight := cell{
+		value: -1,
+	}
+
+	for ci, cv := range b.cells[max.index+1:] {
+		if cv > maxRight.value {
+			maxRight = cell{
+				index: ci,
+				value: cv,
+			}
+		}
+	}
+
+	maxInTensPlace := fmt.Sprintf("%d%d", max.value, maxRight.value)
+	maxInOnesPlace := fmt.Sprintf("%d%d", maxLeft.value, max.value)
+
+	maxInTensPlaceAsNumber, _ := strconv.Atoi(maxInTensPlace)
+	maxInOnesPlaceAsNumber, _ := strconv.Atoi(maxInOnesPlace)
+
+	if maxInTensPlaceAsNumber > maxInOnesPlaceAsNumber {
+		return maxInTensPlaceAsNumber
+	}
+
+	return maxInOnesPlaceAsNumber
+}
+
+func (b bank) Cells() []int {
+	return b.cells
+}