*

1 files changed, 117 insertions, 0 deletions

diff --git a/go/life.go b/go/life.go
new file mode 100644
index 0000000..a4c5b6b
--- /dev/null
+++ b/go/life.go
@@ -0,0 +1,117 @@
+package main
+
+import (
+	"fmt"
+	"time"
+)
+
+const (
+	width  = 10
+	height = 10
+)
+
+type Board [][]bool
+
+func NewBoard() Board {
+	b := make(Board, height)
+	for i := range b {
+		b[i] = make([]bool, width)
+	}
+	return b
+}
+
+// sets a cell to alive
+func (b Board) SetAlive(x, y int) {
+	b[y][x] = true
+}
+
+// asks if a cell is alive
+func (b Board) IsAlive(x, y int) bool {
+	if x < 0 || x >= width || y < 0 || y >= height {
+		return false
+	}
+	return b[y][x]
+}
+
+// finds the next state of the board
+func (b Board) NextState() Board {
+	next := NewBoard()
+	for y := 0; y < height; y++ {
+		for x := 0; x < width; x++ {
+			aliveNeighbors := b.countAliveNeighbors(x, y)
+			if b.IsAlive(x, y) {
+				next[y][x] = aliveNeighbors == 2 || aliveNeighbors == 3
+			} else {
+				next[y][x] = aliveNeighbors == 3
+			}
+		}
+	}
+	return next
+}
+
+// counts the number of alive neighbors for a given cell
+func (b Board) countAliveNeighbors(x, y int) int {
+	count := 0
+	for dy := -1; dy <= 1; dy++ {
+		for dx := -1; dx <= 1; dx++ {
+			if dx == 0 && dy == 0 {
+				continue
+			}
+			if b.IsAlive(x+dx, y+dy) {
+				count++
+			}
+		}
+	}
+	return count
+}
+
+func (b Board) Print() {
+	for y := 0; y < height; y++ {
+		for x := 0; x < width; x++ {
+			if b.IsAlive(x, y) {
+				fmt.Print("O ")
+			} else {
+				fmt.Print(". ")
+			}
+		}
+		fmt.Println()
+	}
+	fmt.Println()
+}
+
+func main() {
+	boards := []Board{
+		NewBoard(),
+		NewBoard(),
+		NewBoard(),
+	}
+
+	// glider
+	boards[0].SetAlive(1, 0)
+	boards[0].SetAlive(2, 1)
+	boards[0].SetAlive(0, 2)
+	boards[0].SetAlive(1, 2)
+	boards[0].SetAlive(2, 2)
+
+	// blinker
+	boards[1].SetAlive(1, 0)
+	boards[1].SetAlive(1, 1)
+	boards[1].SetAlive(1, 2)
+
+	// r-pentomino
+	boards[2].SetAlive(3, 3)
+	boards[2].SetAlive(4, 3)
+	boards[2].SetAlive(2, 4)
+	boards[2].SetAlive(3, 4)
+	boards[2].SetAlive(3, 5)
+
+	// iterate through each board
+	for _, board := range boards {
+		for i := 0; i < 10; i++ {
+			board.Print()
+			board = board.NextState()
+			time.Sleep(time.Second / 2)
+		}
+		fmt.Println("---------------")
+	}
+}