2022 Day 08 Complete!

2022-12-08 08:19:41 -06:00
parent d5aacad011
commit 7c9239ccec
4 changed files with 428 additions and 0 deletions
--- a/2022/day08/main.go
+++ b/2022/day08/main.go
@@ -0,0 +1,169 @@
+package main
+
+import (
+	"fmt"
+
+	h "git.bullercodeworks.com/brian/adventofcode/helpers"
+)
+
+func main() {
+	inp := h.StdinToCoordMap()
+	part1(inp)
+	fmt.Println("")
+	part2(inp)
+}
+
+func part1(inp h.CoordByteMap) {
+	var count int
+	for x := inp.TLX; x <= inp.BRX; x++ {
+		for y := inp.TLY; y <= inp.BRY; y++ {
+			tree := h.Coordinate{X: x, Y: y}
+			if treeIsVisibleFromOutside(inp, tree) {
+				count++
+			}
+		}
+	}
+	fmt.Println("# Part 1")
+	fmt.Println("Visible tree from the outside:", count)
+}
+
+func part2(inp h.CoordByteMap) {
+	var bestScore int
+	var bestTree h.Coordinate
+	for x := inp.TLX; x <= inp.BRX; x++ {
+		for y := inp.TLY; y <= inp.BRY; y++ {
+			tree := h.Coordinate{X: x, Y: y}
+			ss := scenicScore(inp, tree)
+			if ss > bestScore {
+				bestScore = ss
+				bestTree = tree
+			}
+		}
+	}
+
+	fmt.Println("# Part 2")
+	fmt.Println("Best Score:", bestScore, "@", bestTree)
+}
+
+func treeIsVisibleFromOutside(inp h.CoordByteMap, pos h.Coordinate) bool {
+	if pos.X == inp.TLX || pos.X == inp.BRX || pos.Y == inp.TLY || pos.Y == inp.BRY {
+		return true
+	}
+	treeHeight := inp.Get(pos)
+	n, e, s, w := true, true, true, true
+	// Check North
+	for y := inp.TLY; y < pos.Y; y++ {
+		if inp.Get(h.Coordinate{X: pos.X, Y: y}) >= treeHeight {
+			n = false
+			break
+		}
+	}
+	if n {
+		return true
+	}
+	// Check East
+	for x := inp.BRX; x > pos.X; x-- {
+		if inp.Get(h.Coordinate{X: x, Y: pos.Y}) >= treeHeight {
+			e = false
+			break
+		}
+	}
+	if e {
+		return true
+	}
+	// Check South
+	for y := inp.BRY; y > pos.Y; y-- {
+		if inp.Get(h.Coordinate{X: pos.X, Y: y}) >= treeHeight {
+			s = false
+			break
+		}
+	}
+	if s {
+		return true
+	}
+	// Check West
+	for x := inp.TLX; x < pos.X; x++ {
+		if inp.Get(h.Coordinate{X: x, Y: pos.Y}) >= treeHeight {
+			w = false
+			break
+		}
+	}
+	if w {
+		return true
+	}
+	return false
+}
+
+func scenicScore(inp h.CoordByteMap, pos h.Coordinate) int {
+	var n, e, s, w int
+	treeHeight := inp.Get(pos)
+	// Find how many trees we can see to the North
+	if pos.Y == inp.TLY {
+		return 0
+	} else {
+		for y := pos.Y - 1; y >= inp.TLY; y-- {
+			tst := inp.Get(h.Coordinate{X: pos.X, Y: y})
+			if tst < treeHeight {
+				n++
+			} else if tst >= treeHeight {
+				n++
+				break
+			}
+		}
+		if n == 0 {
+			return 0
+		}
+	}
+	// Find how many trees we can see to the East
+	if pos.X == inp.BRX {
+		return 0
+	} else {
+		for x := pos.X + 1; x <= inp.BRX; x++ {
+			tst := inp.Get(h.Coordinate{X: x, Y: pos.Y})
+			if tst < treeHeight {
+				e++
+			} else if tst >= treeHeight {
+				e++
+				break
+			}
+		}
+		if e == 0 {
+			return 0
+		}
+	}
+	// Find how many trees we can see to the South
+	if pos.Y == inp.BRY {
+		return 0
+	} else {
+		for y := pos.Y + 1; y <= inp.BRY; y++ {
+			tst := inp.Get(h.Coordinate{X: pos.X, Y: y})
+			if tst < treeHeight {
+				s++
+			} else if tst >= treeHeight {
+				s++
+				break
+			}
+		}
+		if s == 0 {
+			return 0
+		}
+	}
+	// Find how many trees we can see to the West
+	if pos.X == inp.TLX {
+		return 0
+	} else {
+		for x := pos.X - 1; x >= inp.TLX; x-- {
+			tst := inp.Get(h.Coordinate{X: x, Y: pos.Y})
+			if tst < treeHeight {
+				w++
+			} else if tst >= treeHeight {
+				w++
+				break
+			}
+		}
+		if w == 0 {
+			return 0
+		}
+	}
+	return n * e * s * w
+}