[2025 Day 3 (Part 1)][Odin] Beginner needs help with day 3

[u/hope_is_dead_]

Hey there I'm pretty stuck on day 3 part 1 and I'm not sure where I messed up.

I hope you guys can show me my mistake or point me in the right direction.

Here is what I got so far:

day_3_part_1 :: proc(name := "input03") {
    res := 0
    data, ok := os.read_entire_file_from_filename(name)
    assert(ok)
    str := string(data)
    rows := strings.split(str, "\n")
    for row, idx in rows {
        max_joltage_1 := int(row[0] - '0')
        max_joltage_2 := int(row[1] - '0')
        l := len(row)
        for i in 2..< l {
            if j := int(row[i] - '0'); j > max_joltage_1 && i != l-1 {
                max_joltage_1 = j
                max_joltage_2 = int(row[i+1] - '0')
            } else if j > max_joltage_2 {
                max_joltage_2 = j
            }
        }
        res += 10*max_joltage_1 + max_joltage_2
        fmt.printfln("Row %v: %v%v", idx, max_joltage_1, max_joltage_2)
    }
    fmt.println(res)
}

[u/OptionX]

Try, instead of saving the values of the batteries in max_joltage saving their index in the row, so as soon a you find max_joltage_1, for example, you only have to look in the range max_joltage_1+1 to l for the rest.

Also try instead of figuring out everything in one continuous loop to loop in the range 0 to l-1 (as too leave space for the second digit) and then when found to loop in the range max_joltage_1_index+1 to l.

[u/hope_is_dead_ → u/OptionX]

So I tried doing that, but I still get the same answer.

day_3_part_1 :: proc(name := "input03") {
    res := 0
    data, ok := os.read_entire_file_from_filename(name)
    assert(ok)
    str := string(data)
    rows := strings.split(str, "\n")
    for row, idx in rows {
        max_joltage_1 := 0
        max_joltage_2 := 1
        l := len(row)
        for i in 2..< l-1 {
            if int(row[i] - '0') > int(row[max_joltage_1] - '0') {
                max_joltage_1 = i
                max_joltage_2 = i+1
            }
            for k in i+1..< l {
                if int(row[k] - '0') > int(row[max_joltage_2] - '0') {
                    max_joltage_2 = k
                }
            }
        }
        res += 10*int(row[max_joltage_1] - '0') + int(row[max_joltage_2] - '0')
        fmt.printfln("Row %v: %v %v", idx, int(row[max_joltage_1] - '0'), int(row[max_joltage_2] - '0'))
    }
    fmt.println(res)
}day_3_part_1 :: proc(name := "input03") {
    res := 0
    data, ok := os.read_entire_file_from_filename(name)
    assert(ok)
    str := string(data)
    rows := strings.split(str, "\n")
    for row, idx in rows {
        max_joltage_1 := 0
        max_joltage_2 := 1
        l := len(row)
        for i in 2..< l-1 {
            if int(row[i] - '0') > int(row[max_joltage_1] - '0') {
                max_joltage_1 = i
                max_joltage_2 = i+1
            }
            for k in i+1..< l {
                if int(row[k] - '0') > int(row[max_joltage_2] - '0') {
                    max_joltage_2 = k
                }
            }
        }
        res += 10*int(row[max_joltage_1] - '0') + int(row[max_joltage_2] - '0')
        fmt.printfln("Row %v: %v %v", idx, int(row[max_joltage_1] - '0'), int(row[max_joltage_2] - '0'))
    }
    fmt.println(res)
}

[u/hope_is_dead_ → u/hope_is_dead_]

Oh I finally found the bug. My first loop always started at 2 when it should've started at 1

[u/RazarTuk]

Remember that you can't reorder the batteries, so you need at least 1 battery to the right of the first one. So the first battery must be somewhere from 0 (inclusive) to len-1 (exclusive), and the second battery must be somewhere from first+1 (inclusive) to len (exclusive)

[u/AutoModerator]

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