adventofcode/2018/day03/day03.go

131 lines
2.2 KiB
Go
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package main
import (
"bufio"
"fmt"
"log"
"os"
"strconv"
"strings"
)
func main() {
inp := StdinToStringSlice()
//part1(inp)
part2(inp)
}
var overlaps map[string]bool
func part1(inp []string) {
overlaps = make(map[string]bool)
var allClaims []claim
for _, v := range inp {
c := NewClaim(v)
allClaims = append(allClaims, *c)
}
for _, i := range allClaims {
for _, j := range allClaims {
if i.ID == j.ID {
continue
}
i.findOverlaps(&j)
}
}
fmt.Printf("Overlapping Spots: %d\n", len(overlaps))
}
func part2(inp []string) {
var allClaims []claim
for _, v := range inp {
c := NewClaim(v)
allClaims = append(allClaims, *c)
}
for _, i := range allClaims {
var fail bool
for _, j := range allClaims {
if i.ID == j.ID {
continue
}
if i.intersects(&j) {
fail = true
break
}
}
if !fail {
fmt.Println("Doesn't overlap: " + i.ID)
return
}
}
}
type claim struct {
ID string
X, Y int
Width, Height int
Spots []string
}
func NewClaim(inp string) *claim {
parts := strings.Split(inp, " ")
pos := strings.Split(strings.Trim(parts[2], ":"), ",")
size := strings.Split(parts[3], "x")
x, y, w, h := Atoi(pos[0]), Atoi(pos[1]), Atoi(size[0]), Atoi(size[1])
var spots []string
for i := x; i < (x + w); i++ {
for j := y; j < (y + h); j++ {
spots = append(spots, fmt.Sprintf("%d;%d", i, j))
}
}
return &claim{
ID: parts[0][1:],
X: x,
Y: y,
Width: w,
Height: h,
Spots: spots,
}
}
func (c *claim) intersects(other *claim) bool {
for _, i := range c.Spots {
for _, j := range other.Spots {
if i == j {
return true
}
}
}
return false
}
func (c *claim) findOverlaps(other *claim) bool {
var ret bool
for _, i := range c.Spots {
for _, j := range other.Spots {
if i == j {
overlaps[i] = true
ret = true
}
}
}
return ret
}
func StdinToStringSlice() []string {
var input []string
scanner := bufio.NewScanner(os.Stdin)
for scanner.Scan() {
input = append(input, scanner.Text())
}
return input
}
func Atoi(i string) int {
var ret int
var err error
if ret, err = strconv.Atoi(i); err != nil {
log.Fatal("Invalid Atoi")
}
return ret
}