I apologise if this has already been asked before, but I was unable to find a conclusive answer after some extensive searching, so I thought I would ask here. I am a beginner to Java (to coding, in general) and was tasked with writing a program that takes a user-inputted 3 digit number, and adds those three digits.
Note: I cannot use loops for this task, and the three digits must all be inputted at once.
String myInput;
myInput =
JOptionPane.showInputDialog(null,"Hello, and welcome to the ThreeDigit program. "
+ "\nPlease input a three digit number below. \nThreeDigit will add those three numbers and display their sum.");
int threedigitinput;
threedigitinput = Integer.parseInt(myInput);
解决方案
There are a number of ways, one of which would be...
String ss[] = "123".split("");
int i =
Integer.parseInt(ss[0]) +
Integer.parseInt(ss[1]) +
Integer.parseInt(ss[2]);
System.out.println(i);
another would be...
String s = "123";
int i =
Character.getNumericValue(s.charAt(0)) +
Character.getNumericValue(s.charAt(1)) +
Character.getNumericValue(s.charAt(2));
System.out.println(i);
and still another would be...
String s = "123";
int i =
s.charAt(0) +
s.charAt(1) +
s.charAt(2) -
(3 * 48);
System.out.println(i);
BUT hard coding for 3 numbers isn't very useful beyond this simple case. So how about recursion??
public static int addDigis(String s) {
if(s.length() == 1)
return s.charAt(0) - 48;
return s.charAt(0) - 48 + addDigis(s.substring(1, s.length()));
}
Output for each example: 6
