/* package whatever; // don't place package name! */
 
import java.util.*;
import java.lang.*;
import java.io.*;
import java.util.regex.*;
 
/* Name of the class has to be "Main" only if the class is public. */
class Ideone
{
	public static void main (String[] args) throws java.lang.Exception
	{
		String str = "The problem is that it correctly gives a match for 5,6,7,8 etc but not for 17 or 251 for example. 0,1,2,3,4,9,11,12,13,14,15,16,18,19,250";
		Pattern p = Pattern.compile("\\b(?:[0-49]|1[1-689]|250)\\b|(\\d+)");
		Matcher m = p.matcher(str);
 
		while (m.find() && m.group(1) != null) {
			System.out.print(m.group(1) + " ");
		}
	}
}

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