Java Programs Made Easy

Q)... Get a input string. Find if it is a negative number, if true return the absolute value, in other cases return -1.
input: "-123"
output: 123
input: "@123"
output: -1

1. package Set1;
2. import java.util.*;
3. public class ClassSet27 {
4.  public static int negativeString(String s1){
5.   int n1=0;
6.   if(s1.startsWith("-")){
7.   int n=Integer.parseInt(s1);
8.   if(n<0)
9.    n1=Math.abs(n);}
10.   else
11.    n1=-1;
12.   return n1;
13.  }
14. public static void main(String[] args) {
15.   Scanner s=new Scanner(System.in);
16.   String s1=s.next();
17.   System.out.println(negativeString(s1));
18.  }
19. }