ACM-3n+1 Problem

It is a Java solution.
You should focus on the green part and fix input part for your use.

package acm;

import java.io.*;
import java.util.*;

public class ThreeNPlusOne {
 public static void main(String[] args) throws IOException {
  ArrayList<String> userInput = new ArrayList<String>();
  int intCases = 0;
  System.out.println("How many test cases to run?");
  BufferedReader bs = new BufferedReader(new InputStreamReader(System.in));
  String cases = bs.readLine();
  intCases = Integer.parseInt(cases);
  while (intCases != userInput.size()) {
   System.out
     .println("Please enter 2 numbers m and n,separate them by dot.");
   userInput.add(bs.readLine());
  }
  Iterator it = userInput.iterator();
  while (it.hasNext()) {
   String numbers = (String) (it.next());
   int[] ns = getInts(numbers);
   int first = ns[0];
   int second = ns[1];
   System.out.println(first + " " + second + " "+ threeN(first, second));
  }

 }

 public static int threeN(int a, int b) {
  int max= 0;
  for (int i = a; i <= b; ) {
   int tmp=i;
   int count = 0;
   while (true) {
    count++;
    if (i == 1) {
     break;
    } else {
     if (i % 2 != 0) {
      i = 3 * i + 1;
     } else {
      i /= 2;
     }
    }
   }
   if (count > max) {
    max = count;
   }
   i=++tmp;
  }
  return max;
 }

 public static int[] getInts(String str) {
  int totalNumbers = str.split(",").length;
  int[] ints = new int[totalNumbers];
  for (int i = 0; i < totalNumbers; i++) {
   ints[i] = Integer.parseInt(str.split(",")[i].trim());
  }
  return ints;
 }

}