days 13,14,15

14/14.go

@@ -0,0 +1,131 @@
+package main
+
+import (
+	"fmt"
+	"os"
+	//"strconv"
+)
+
+// go run 14.go "input"
+
+func main() {
+
+	s := os.Args[1]
+	ones := 0
+
+	squareSize := 128
+	grid := make([][]int, squareSize)
+
+	for x := 0; x < squareSize; x++ {
+		lineSeed := fmt.Sprint(s, "-", x)
+		hash := MakeHash(lineSeed)
+		ones += CountOnes(hash)
+		grid[x] = BuildGrid(hash)
+	}
+
+	regionCount := 1
+	for y := 0; y < squareSize; y++ {
+		for x := 0; x < squareSize; x++ {
+			grid, regionCount = CountRegions(grid, x, y, regionCount)
+		}
+	}
+
+	fmt.Println(ones)
+	fmt.Println(regionCount-1)
+
+}
+
+func CountRegions (grid [][]int, x int, y int, regionCount int) ([][]int, int) {
+	if x < 0 || x >= len(grid) || y < 0 || y >= len(grid) {
+		return grid,regionCount
+	}
+
+	if grid[x][y] == -1 {
+		return grid, regionCount
+	}
+
+	if grid[x][y] == 0 {
+		grid[x][y] = regionCount
+		grid,_ = CountRegions(grid, x+1, y, regionCount)
+		grid,_ = CountRegions(grid, x-1, y, regionCount)
+		grid,_ = CountRegions(grid, x, y+1, regionCount)
+		grid,_ = CountRegions(grid, x, y-1, regionCount)
+		regionCount++
+	}
+	
+	return grid, regionCount
+}
+
+func BuildGrid (s string) []int {
+	y := make([]int, len(s))
+
+	for i := range s {
+		if s[i] == 49 {
+			y[i] = 0
+		} else {
+			y[i] = -1
+		}
+	}
+
+	return y
+}
+
+func CountOnes (s string) int {
+	count := 0
+	for x := range s {
+		if s[x] == 49 {
+			count++
+		}
+	}
+	return count
+}
+
+
+func MakeHash (s string) string {
+
+	size := 256
+	appendList := []byte{17, 31, 73, 47, 23}
+
+	s = s + string(appendList)
+
+	list := make([]int, size)
+	for i := 0; i < size; i++ {
+		list[i] = i
+	}
+
+	pos := 0
+	skip := 0
+
+	for j := 0; j < 64; j++ {
+		for x := range s {
+
+			i := int(s[x])
+
+			// Reverse the section
+			r := i/2
+			
+			for y := 0; y < r; y++ {
+				bottom := (pos+y) % size
+				top := (pos+i-y-1) % size
+				tmp := list[bottom]
+				list[bottom] = list[top]
+				list[top] = tmp
+			}
+
+			pos = (pos+i+skip) % size
+			skip++
+		}
+	}
+
+	ret := ""
+	for a:=0; a<16; a++ {
+		r := list[a*16]
+		for b:=1; b<16; b++ {
+			xorpos := (a*16)+b
+			r = r ^ list[xorpos]
+		}
+		ret = ret + fmt.Sprintf("%08b", r) //+ " "
+	}
+	return ret
+
+}