[LeetCode] Restore IP Addresses

Given a string containing only digits, restore it by returning all possible valid IP address combinations.

For example:
Given "25525511135",

return ["255.255.11.135", "255.255.111.35"]. (Order does not matter)

[Solution].java

public class Solution {
    public ArrayList<String> restoreIpAddresses(String s) {
        // Note: The Solution object is instantiated only once and is reused by each test case.
        ArrayList<String> output = new ArrayList<String>();
        parse(s, 0, 0, true, 0, new int[4], output);
        return output;
    }
    
    public void parse(String s, int pos, int last, boolean start, int temp_index, int[] temp, ArrayList<String> output){
        if(pos == s.length()){
            if(temp_index == temp.length && start){
                output.add(temp[0] + "." + temp[1] + "." + temp[2] + "." + temp[3]);
            }
            return;
        }
        
        if(temp_index == temp.length) return;
        
        if(last == 0 && !start){
            temp[temp_index] = 0;
            parse(s, pos, 0, false, temp_index + 1, temp, output);
        }
        else{
            int now = last * 10 + s.charAt(pos) - 48;
            if(now > 255) return;
            //stop here
            temp[temp_index] = now;
            parse(s, pos + 1, 0, true, temp_index + 1, temp, output);
            //mach to next pos
            parse(s, pos + 1, now, false, temp_index, temp, output);
        }
    }
}