81 lines
1.5 KiB
Go
81 lines
1.5 KiB
Go
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package day_07
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import (
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"strconv"
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"strings"
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)
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type Equation struct {
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Result int
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Variables []int
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}
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// task:https://adventofcode.com/2024/day/7
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func SolveBasic(input string) int {
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equations := loadEquations(input)
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sum := 0
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for _, equation := range equations {
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if Solvable(equation) {
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sum += equation.Result
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}
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}
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return sum
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}
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func Solvable(equation Equation) bool {
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for i := 0; i < 1<<(len(equation.Variables)-1); i++ {
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if solvable(equation, i) {
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return true
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}
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}
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return false
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}
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func solvable(equation Equation, options int) bool {
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sum := equation.Variables[0]
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for i := 0; i < len(equation.Variables)-1; i++ {
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if sum > equation.Result {
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return false
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}
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if options&(1<<i) != 0 {
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sum *= equation.Variables[i+1]
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} else {
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sum += equation.Variables[i+1]
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}
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}
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return sum == equation.Result
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}
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// task:https://adventofcode.com/2024/day/7#part2
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func SolveComplex(input string) int {
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return 0
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}
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func loadEquations(input string) (equations []Equation) {
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lines := strings.Split(input, "\n")
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for _, line := range lines {
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equations = append(equations, loadEquation(line))
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}
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return
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}
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func loadEquation(line string) Equation {
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substrings := strings.Split(line, ": ")
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equation := Equation{
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Result: must(strconv.Atoi(substrings[0])),
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}
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for _, param := range strings.Split(substrings[1], " ") {
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equation.Variables = append(equation.Variables, must(strconv.Atoi(param)))
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}
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return equation
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}
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func must(val int, err error) int {
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if err != nil {
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panic(err)
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}
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return val
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}
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