86 lines
1.3 KiB
Go
86 lines
1.3 KiB
Go
|
|
||
|
|
package part1
|
||
|
|
|
||
|
|
import (
|
||
|
|
"bufio"
|
||
|
|
"strings"
|
||
|
|
"strconv"
|
||
|
|
"os"
|
||
|
|
"errors"
|
||
|
|
"fmt"
|
||
|
|
)
|
||
|
|
|
||
|
|
func main() {
|
||
|
|
reader := bufio.NewReader(os.Stdin);
|
||
|
|
total := 0;
|
||
|
|
for {
|
||
|
|
line, err := reader.ReadString('\n');
|
||
|
|
if (err != nil) {
|
||
|
|
break
|
||
|
|
}
|
||
|
|
values, err := LineConv(line)
|
||
|
|
if err != nil {
|
||
|
|
fmt.Println(err)
|
||
|
|
return
|
||
|
|
}
|
||
|
|
next, err := Next(values)
|
||
|
|
if err != nil {
|
||
|
|
fmt.Println(err)
|
||
|
|
return
|
||
|
|
}
|
||
|
|
total += next;
|
||
|
|
fmt.Printf("%v => %v\n", values, next)
|
||
|
|
}
|
||
|
|
println(total)
|
||
|
|
return
|
||
|
|
}
|
||
|
|
|
||
|
|
func Next(src []int) (int, error) {
|
||
|
|
if len(src) < 2 {
|
||
|
|
return 0, errors.New("not enough data!")
|
||
|
|
}
|
||
|
|
if IsZero(src) {
|
||
|
|
return 0, nil
|
||
|
|
}
|
||
|
|
deriv := Deriv(src)
|
||
|
|
nextDelta, err := Next(deriv)
|
||
|
|
if (err != nil) {
|
||
|
|
return 0, err
|
||
|
|
}
|
||
|
|
return src[len(src)-1] + nextDelta, nil
|
||
|
|
}
|
||
|
|
|
||
|
|
func Deriv(src []int) (deriv []int) {
|
||
|
|
for i := range src {
|
||
|
|
if i == len(src)-1 {
|
||
|
|
break
|
||
|
|
}
|
||
|
|
deriv = append(deriv, src[i+1] - src[i])
|
||
|
|
}
|
||
|
|
return
|
||
|
|
}
|
||
|
|
|
||
|
|
func IsZero(src []int) bool {
|
||
|
|
res := true
|
||
|
|
for _,v := range src {
|
||
|
|
if v != 0 {
|
||
|
|
res = false
|
||
|
|
}
|
||
|
|
}
|
||
|
|
return res
|
||
|
|
}
|
||
|
|
|
||
|
|
func LineConv(line string) ( []int, error ) {
|
||
|
|
strs := strings.Split(strings.Trim(line, "\n"), " ")
|
||
|
|
values := []int{};
|
||
|
|
for _, str := range strs {
|
||
|
|
value, err := strconv.Atoi(str)
|
||
|
|
if (err != nil) {
|
||
|
|
return []int{}, err
|
||
|
|
}
|
||
|
|
values = append(values, value)
|
||
|
|
}
|
||
|
|
return values, nil;
|
||
|
|
}
|
||
|
|
|