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package main
import (
"bufio"
"fmt"
"os"
"strconv"
"strings"
)
func IntAbs(a int) int {
if a >= 0 {
return a
}
return -a
}
func main() {
lists := readData("data.txt")
fmt.Println(doTheThing(lists, 0))
fmt.Println(doTheThing(lists, 1))
}
func readData(fileName string) (list [][]int) {
fp, err := os.Open(fileName)
if err != nil {
panic(err)
}
scanner := bufio.NewScanner(fp)
list = make([][]int, 0)
for scanner.Scan() {
line := strings.TrimSpace(scanner.Text())
sublist := make([]int, 0)
for _, n := range strings.Split(line, " ") {
value, err := strconv.Atoi(n)
if err != nil {
panic(err)
}
sublist = append(sublist, value)
}
list = append(list, sublist)
}
return
}
func doTheThing(list [][]int, canSkip int) (valid int) {
for _, l := range list {
if isValid(l, canSkip, -1) {
valid += 1
}
}
return
}
func isValid(l []int, canSkip int, toSkip int) bool {
sumDiff := 0
sumAbsDiff := 0
for i := 0; i < len(l)-1; i++ {
if i == toSkip {
continue
}
j := i + 1
if j == toSkip {
j += 1
if j >= len(l) {
continue
}
}
diff := l[i] - l[j]
if diff == 0 || IntAbs(diff) > 3 || IntAbs(sumDiff+diff) != sumAbsDiff+IntAbs(diff) {
if canSkip > 0 {
return isValid(l, canSkip-1, i-1) || isValid(l, canSkip-1, i) || isValid(l, canSkip-1, j)
} else {
return false
}
}
sumDiff += diff
sumAbsDiff += IntAbs(diff)
}
return true
}
|
