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package main
import (
"bufio"
"fmt"
"os"
"strconv"
"strings"
)
func main() {
fmt.Println(part1(readData("example.txt"), 11, 7), 12)
fmt.Println(part1(readData("data.txt"), 101, 103))
part2(readData("data.txt"), 101, 103)
}
type Bot struct {
x, y int
dx, dy int
}
func part1(bots []Bot, w, h int) int {
q1, q2, q3, q4 := 0, 0, 0, 0
hw := w / 2
hh := h / 2
for _, b := range bots {
x := ((b.x+b.dx*100)%w + w) % w
y := ((b.y+b.dy*100)%h + h) % h
if x > hw {
if y < hh {
q2++
} else if y > hh {
q4++
}
} else if x < hw {
if y < hh {
q1++
} else if y > hh {
q3++
}
}
}
return q1 * q2 * q3 * q4
}
func part2(bots []Bot, w, h int) {
fp, err := os.Create("output.txt")
if err != nil {
panic(err)
}
buffer := make([]byte, (w+1)*h)
for y := range h {
buffer[y*(w+1)+w] = '\n'
}
for i := range 10000 {
for y := range h {
for x := range w {
buffer[y*(w+1)+x] = ' '
}
}
for _, b := range bots {
x := ((b.x+b.dx*i)%w + w) % w
y := ((b.y+b.dy*i)%h + h) % h
buffer[y*(w+1)+x] = 'X'
}
// So fucking stupid
if strings.Index(string(buffer), "XXXXXXXX") >= 0 {
fmt.Println(i)
fmt.Fprintln(fp, i)
fp.Write(buffer)
}
}
}
func parsePair(s string) (x, y int) {
nums := strings.Split(s[2:], ",")
x, _ = strconv.Atoi(nums[0])
y, _ = strconv.Atoi(nums[1])
return
}
func readData(fileName string) (bots []Bot) {
fp, _ := os.Open(fileName)
scanner := bufio.NewScanner(fp)
for scanner.Scan() {
line := strings.Split(strings.TrimSpace(scanner.Text()), " ")
x, y := parsePair(line[0])
dx, dy := parsePair(line[1])
bots = append(bots, Bot{x, y, dx, dy})
}
return
}
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