Regex to match continuous pattern of integer then space

Question

I\'m asking the user for input through the Scanner in Java, and now I want to parse out their selections using a regular expression. In essence, I show them an enu

Answer 1

Pattern pattern = new Pattern(^([0-9]*\s+)*[0-9]*$)

Explanation of the RegEx:

• ^ : beginning of input
• [0-9] : only digits
• '*' : any number of digits
• \s : a space
• '+' : at least one space
• '()*' : any number of this digit space combination
• $: end of input

This treats all of the following inputs as valid:

• "1"
• "123 22"
• "123 23"
• "123456 33 333 3333 "
• "12321 44 452 23 "

etc.