/* 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 s = "123456abc:de234567:c567890d";
		StringBuilder result = new StringBuilder();
		Pattern pattern = Pattern.compile("(?<!\\d)\\d{6}(?!\\d)");
		Matcher matcher = pattern.matcher(s);
		while (matcher.find()){
			if (result.length() == 0)  {
				result.append(matcher.group(0));
			} else {
			   result.append("-").append(matcher.group(0));
			}
		} 
		System.out.println(result.toString());
	}
}

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