2021 Day 25 Complete

2021/day25/main.go

@@ -0,0 +1,74 @@
+package main
+
+import (
+	"fmt"
+
+	h "git.bullercodeworks.com/brian/adventofcode/helpers"
+)
+
+func main() {
+	fmt.Println("vim-go")
+	inp := h.StdinToStringSlice()
+	field := h.StringSliceToCoordByteMap(inp)
+	part1(field)
+}
+
+func part1(f h.CoordByteMap) {
+	// Run until no cucumbers move
+	var steps int
+	var done bool
+	for !done {
+		east := f.FindAll('>')
+		eastMovers := make(map[h.Coordinate]h.Coordinate)
+		for i := range east {
+			var check h.Coordinate
+			if east[i].X == f.BRX {
+				check = h.Coordinate{
+					X: f.TLX,
+					Y: east[i].Y,
+				}
+			} else {
+				check = east[i].East()
+			}
+			if f.Get(check) == '.' {
+				eastMovers[east[i]] = check
+			}
+		}
+		if len(eastMovers) == 0 {
+			done = true
+		} else {
+			for k, v := range eastMovers {
+				f.Put(k, '.')
+				f.Put(v, '>')
+			}
+		}
+
+		south := f.FindAll('v')
+		southMovers := make(map[h.Coordinate]h.Coordinate)
+		for i := range south {
+			var check h.Coordinate
+			if south[i].Y == f.BRY {
+				check = h.Coordinate{
+					X: south[i].X,
+					Y: f.TLY,
+				}
+			} else {
+				check = south[i].South()
+			}
+			if f.Get(check) == '.' {
+				southMovers[south[i]] = check
+			}
+		}
+		if len(southMovers) == 0 {
+			done = done && true
+		} else {
+			for k, v := range southMovers {
+				f.Put(k, '.')
+				f.Put(v, 'v')
+			}
+		}
+		steps++
+	}
+	fmt.Println("# Part 1")
+	fmt.Println("Stable after", steps, "steps")
+}