tell me the number

Define the function S(x) as the sum of the squares of the digits of x.
For example: S(3)=3*3=9 and S(230)=2*2+3*3+0*0=13.

Define the set T(x) to be the set of unique numbers that are produced by
repeatedly applying S to x. That is: S(x), S(S(x)), S(S(S(x))), etc...
For example, repeatedly applying S to 37:
S(37)=3*3+7*7=58.
S(58)=5*5+8*8=89.
S(89)=145.
S(145)=42.
S(42)=20.
S(20)=4.
S(4)=16.
S(16)=37.
Note this sequence will repeat so we can stop calculating now and:
T(37)={58,89,145,42,20,4,16,37}.
However, note T(x) may not necessarily contain x.

Implement a class SquareDigits, which contains a method smallestResult. The
method takes an int, n, as a parameter and returns the smallest int, x, such
that T(x) contains n.

The method signature is (be sure your method is public):
int smallestResult(int n);

TopCoder will ensure n is non-negative and is between 0 and 199 inclusive.

Examples:
If n=0: S(0) = 0, so T(0)={0}, so the method should return 0.

If n=2: T(0) through T(10) do not contain the value 2. If x=11, however:
S(11)=1*1+1*1=2, so T(11) contains 2, and the method should return 11.

If n=10: T(0) through T(6) do not contain 10. If x=7:
S(7)=49.
S(49)=97.
S(97)=130.
S(130)=10.
S(10)=1.
and it starts to repeat...
so T(7) is {49,97,130,10,1}, which contains 10, and the method should return 7.

n=1 -> x=1
n=19 -> x=133
n=85 -> x=5
n=112 -> x=2666


Here's the prog

import java.io.*;
import java.util.*;
public class SquareDigits
{
public int S(int x)
{
int result=0;
while(x/10>0)
{
result=result+(x%10)*(x%10);
x=x/10;
}
result=result+x*x;
return result;
}

public int smallestResult(int input_num)
{
int result,count;
for(count=0;;count++)
{
result=count;
Set T=new HashSet();
do{
result=S(result);

}while(T.add(result));
if(T.contains(input_num))
return count;


}
}
public static void main(String args[])
{
int input_num=0, answer;
String inputstring;
SquareDigits instan=new SquareDigits();
try
{
BufferedReader br=new BufferedReader(new InputStreamReader(System.in));
inputstring=br.readLine();
input_num=Integer.parseInt(inputstring);
}
catch(IOException e)
{
System.out.println("i/o exception catched");
}
answer=instan.smallestResult(input_num);
System.out.println("the answer is "+answer);


}

}