129 lines
2.2 KiB
Go
129 lines
2.2 KiB
Go
|
package main
|
||
|
|
|
||
|
|
import (
|
||
|
|
"bufio"
|
||
|
|
"fmt"
|
||
|
|
"log"
|
||
|
|
"os"
|
||
|
|
"strconv"
|
||
|
|
"strings"
|
||
|
|
)
|
||
|
|
|
||
|
|
var progs map[int][]int
|
||
|
|
var groups map[int][]int
|
||
|
|
|
||
|
|
func main() {
|
||
|
|
inp := StdinToStrings()
|
||
|
|
part1(inp)
|
||
|
|
part2()
|
||
|
|
}
|
||
|
|
|
||
|
|
func part1(inp []string) {
|
||
|
|
progs = make(map[int][]int)
|
||
|
|
for i := range inp {
|
||
|
|
pts := strings.Split(inp[i], " ")
|
||
|
|
mn := Atoi(pts[0])
|
||
|
|
|
||
|
|
for _, v := range pts[2:] {
|
||
|
|
if v[len(v)-1] == ',' {
|
||
|
|
v = v[:len(v)-1]
|
||
|
|
}
|
||
|
|
if v = strings.TrimSpace(v); v != "" {
|
||
|
|
sub := Atoi(v)
|
||
|
|
progs[mn] = append(progs[mn], sub)
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
var res int
|
||
|
|
for k := range progs {
|
||
|
|
if pRes, _ := progCanAccess(k, 0, []int{}); pRes {
|
||
|
|
res++
|
||
|
|
}
|
||
|
|
}
|
||
|
|
fmt.Println(res, "programs can access zero")
|
||
|
|
}
|
||
|
|
|
||
|
|
func part2() {
|
||
|
|
groups = make(map[int][]int)
|
||
|
|
for k, v := range progs {
|
||
|
|
isNew := true
|
||
|
|
for gk := range groups {
|
||
|
|
if can, _ := progCanAccess(k, gk, []int{}); can {
|
||
|
|
AddToGroup(gk, k)
|
||
|
|
isNew = false
|
||
|
|
break
|
||
|
|
}
|
||
|
|
}
|
||
|
|
if isNew {
|
||
|
|
// We went through all groups and couldn't access any
|
||
|
|
groups[k] = v
|
||
|
|
}
|
||
|
|
}
|
||
|
|
fmt.Println(len(groups), "total groups")
|
||
|
|
}
|
||
|
|
|
||
|
|
func AddToGroup(grp, prog int) {
|
||
|
|
if !SliceContains(groups[grp], prog) {
|
||
|
|
groups[grp] = append(groups[grp], prog)
|
||
|
|
}
|
||
|
|
for _, v := range progs[prog] {
|
||
|
|
if !SliceContains(groups[grp], v) {
|
||
|
|
groups[grp] = append(groups[grp], v)
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
func progCanAccess(st, end int, tried []int) (bool, []int) {
|
||
|
|
// Have we already tried this one?
|
||
|
|
if SliceContains(tried, st) {
|
||
|
|
return false, tried
|
||
|
|
}
|
||
|
|
tried = append(tried, st)
|
||
|
|
|
||
|
|
// Is this it?
|
||
|
|
if st == end {
|
||
|
|
return true, tried
|
||
|
|
}
|
||
|
|
|
||
|
|
// Is it direct?
|
||
|
|
if SliceContains(progs[st], end) {
|
||
|
|
return true, tried
|
||
|
|
}
|
||
|
|
|
||
|
|
// Ok, recurse
|
||
|
|
var res bool
|
||
|
|
for _, v := range progs[st] {
|
||
|
|
if res, tried = progCanAccess(v, end, tried); res {
|
||
|
|
return res, tried
|
||
|
|
}
|
||
|
|
}
|
||
|
|
return false, tried
|
||
|
|
}
|
||
|
|
|
||
|
|
func SliceContains(sl []int, tgt int) bool {
|
||
|
|
for i := range sl {
|
||
|
|
if sl[i] == tgt {
|
||
|
|
return true
|
||
|
|
}
|
||
|
|
}
|
||
|
|
return false
|
||
|
|
}
|
||
|
|
|
||
|
|
func StdinToStrings() []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
|
||
|
|
}
|