I am working on a simple project in Java which need to take in a string through a Scanner object and then sort out the inputs which can be integers. These then need to be fed in pairs to run the program (which needs 2 input parameters).
An input could be: 2 4 % # -3 -5 q
which then needs to result in 2, 4, -3, -5 and q for quit. The rest needs to be sorted away and is not used.
How can I do this?
String input = "2 4 % # -3 -5 q";
String formatted = input.replaceAll("[^ 0-9q-]", "").replaceAll(" +", " ");
String[] split = formatted.split(" ");
// Loop through split
Our first goal is to remove everything that is uneccessary, to do that here's the regex I used in detail
^ - Replace all the characters that are not equal to the characters provided in the regex.
- Keep all spaces0-9 - Keep all numbersq - Keep all of the letter q- - Keep all hyphensSince we kept all spaces we will end up with the String 2 4 -3 -5 q. The spaces in between will cause an issue when we try to split it, so we replaces all multiple spaces (using the regex +) with a single space.
Now you can loop through split and pair them.
For the given input of 2 4 U s -4 6 a b c 10 100 3 -1 s q
Scanner scanner = new Scanner(System.in);
String input;
while (!(input = scanner.next()).equalsIgnoreCase("q")) {
if (input.matches("(\\+|-)?\\d+")) {
System.out.print(input + " ");
}
}
System.out.println();
prints
2 4 -4 6 10 100 3 -1
