3n+1 problem by Java

這是ACM上面比較簡單的題目
程式功力尚須加強


import java.io.* ;
public class nnn1
{
 public static void main(String args[]) throws IOException
 {
  System.out.println("Please input a number:");
  BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
  String str2 = br.readLine();
  String str1 = br.readLine();
  int small_num = Integer.parseInt(str2);
  int num = Integer.parseInt(str1);
  System.out.println(small_num+" "+num);
  int temp;
 int max_count =0;//紀錄最大運算次數
 if(small_num > num)//輸入數字大小順序對調皆可
 {
  temp = small_num;
  small_num = num;
  num = temp;
 }
// System.out.println(small_num+" "+num);

 for(int j=small_num;j<=num;j++)//每個數字的計算過程以及次數
 {
  int count =1;
  int number = j;

  System.out.println(number);
     do
     {
      //System.out.println(num);
      if ( number== 1 )
       {break;}
      if(number%2==1)
      {
      number = 3*number+1;
      }
      else
      {
      number = number/2;
      }
      count++; 
     }while(true);
   
 
  System.out.println("count is "+count);
 
if(count > max_count)
{
max_count = count;
}
  }//是forloop的大括號
  System.out.println("Max count is "+max_count);
 }
}