79 lines
1.6 KiB
Go
79 lines
1.6 KiB
Go
package main
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import (
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"strconv"
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"strings"
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"github.com/jpillora/puzzler/harness/aoc"
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)
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func main() {
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aoc.Harness(run)
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}
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// on code change, run will be executed 4 times:
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// 1. with: false (part1), and example input
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// 2. with: true (part2), and example input
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// 3. with: false (part1), and user input
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// 4. with: true (part2), and user input
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// the return value of each run is printed to stdout
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func run(part2 bool, input string) any {
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// when you're ready to do part 2, remove this "not implemented" block
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data := make([][]int, 0)
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for _, line := range strings.Split(input, "\n") {
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dataLine := make([]int, 0)
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for _, s := range strings.Split(line, " ") {
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d, _ := strconv.Atoi(s)
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dataLine = append(dataLine, d)
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}
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data = append(data, dataLine)
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}
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if part2 {
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return "not implemented"
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}
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// solve part 1 here
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sumNexts := 0
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for _, d := range data {
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sumNexts += getNext(d)
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}
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return sumNexts
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}
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func getNext(data []int) int {
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diffTriangle := make([][]int, 0)
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diffTriangle = append(diffTriangle, data)
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for !allZero(diffTriangle[len(diffTriangle)-1]) {
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diffTriangle = append(diffTriangle, getDiffs(diffTriangle[len(diffTriangle)-1]))
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//fmt.Printf("%v\n", diffTriangle[len(diffTriangle)-1])
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}
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add := 0
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for i := len(diffTriangle) - 2; i >= 0; i -= 1 {
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add += diffTriangle[i][len(diffTriangle[i])-1]
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}
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return add
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}
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func getDiffs(data []int) []int {
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nextData := make([]int, 0)
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for i := 0; i < len(data)-1; i += 1 {
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nextData = append(nextData, data[i+1]-data[i])
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}
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return nextData
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}
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func allZero(data []int) bool {
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for _, d := range data {
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if d != 0 {
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return false
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}
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}
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return true
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}
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