AdventOfCode2k16/d02/d02.go

package main

import "bufio"
import "fmt"
import "os"

type Digicode struct {
    mat [][]string
    result string
    pos []int
}

func NewDigicode() Digicode {
    var res Digicode
    /** First case */
    /*
    res.pos = []int { 1, 1 }
    res.mat = append(res.mat, []string{"1", "2", "3"})
    res.mat = append(res.mat, []string{"4", "5", "6"})
    res.mat = append(res.mat, []string{"7", "8", "9"})
    */

    /** second case */
    res.pos = []int { 2, 0 }
    res.mat = append(res.mat, []string{".", ".", "1", ".", "."})
    res.mat = append(res.mat, []string{".", "2", "3", "4", "."})
    res.mat = append(res.mat, []string{"5", "6", "7", "8", "9"})
    res.mat = append(res.mat, []string{".", "A", "B", "C", "."})
    res.mat = append(res.mat, []string{".", ".", "D", ".", "."})
    return res
}

func (this *Digicode) NextDigit(line string) {
    code := make(map[rune][]int)

    code['U'] = []int { -1, 0  }
    code['D'] = []int {  1, 0  }
    code['L'] = []int {  0, -1 }
    code['R'] = []int {  0, 1  }

    for _, dir := range(line) {
        if (this.pos[0] + code[dir][0] < 0 ||
            this.pos[1] + code[dir][1] < 0 ||
            this.pos[0] + code[dir][0] >= len(this.mat) ||
            this.pos[1] + code[dir][1] >= len(this.mat[this.pos[0] + code[dir][0]])) {
            continue
        }
        newCode := []int { this.pos[0] + code[dir][0], this.pos[1] + code[dir][1]}
        if (this.mat[newCode[0]][newCode[1]] == ".") {
            continue
        }
        this.pos = newCode
    }
    this.result += this.mat[this.pos[0]][this.pos[1]]
}

func main() {
    reader := bufio.NewReader(os.Stdin)
    code := NewDigicode()

    for true {
        read, _, err := reader.ReadLine()
        if len(read) > 0 {
            code.NextDigit(string(read))
        }
        if (err != nil) {
            break
        }
    }

    fmt.Println("output: ", code.result)
}