Input format is like this
Input:
30 120.00
When you use in.readLine() it reads the whole line from input “30 120.00” , so when you use Integer.parseInt it throws an exception as the argument is not an integer. You need to separate the two numbers.
Use something like
String s[]=in.readLine().split(" ");
int withdraw = Integer.parseInt(s[0]);
double balance = Double.parseDouble(s[1]);