How Can I use for-loop to solve this task?

I have a txt file which contains only integers. Each line contains 1 integer.
The txt file is representing pits and their depth in the ground:

For example:
0
0
0
1
2
2
2
2
2
2
3
2
2
1
0

In this case, the pit starts from the index 3 and ends at index 13.
Lets say the user input is 10. The depth of the pit is 2m at index 10.
From the 10. index I need to go backwards until I reach the index with value of 0 to determinate the beginig of the pit. After I need to go forward until I reach 0 again to determinate the end of the pit.
How would you go about this?

int in = sc.nextInt();
int input = Integer.parseInt(data.get(in - 1));
if (input == 0) {
    System.out.println("There is no pit at this index!");
}

for (int i = input; i < data.size(); i--) {
    if (Integer.parseInt(data.get(i)) == 0) {
        System.out.println("The first index of the pit : " + data.get(i + 1));
    }
}

Upon thinking about this some, I came up with an improved solution which does not require storage of the values nor does it require multiple loops.
This presumes that the first element in the file is the starting position (threshold) and what follows are the depths. It is up to you to make adjustments to suit your situation.

• The basic idea is to read in the values until the threshold is reached, only changing start if a depth of 0 occurs.
• Once the threshold is met, simply continue reading until a depth of 0 is found or until the end of file is reached, incrementing end as appropriate

String fileName = "<your filename>";
try (Scanner in = new Scanner(new File(fileName))) {
    int threshold = in.nextInt();
    int index = 0;
    int end = 0;
    int start = 0;
    while (in.hasNextInt()) {
       int depth = in.nextInt();
       if (depth == 0 && index < threshold) {
           start = index+1;
       }
       if (index >= threshold && depth == 0) {
          break;
       }
       end = index;
       index++;
    }
    if (end < threshold) {
        System.out.printf("No pit at index %d%n", threshold);
    } else {
        System.out.printf("Pit starts at index %d and ends at index %d%n",
                start, end);
    }
} catch (FileNotFoundException fne) {
    fne.printStackTrace();
}

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