/* 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 rx = "(?i)w(?:e{2})?k(\\d+)(?:(?:\\s*until\\s*|[ _\\/])(?:w(?:e{2})?k)?(\\d+))?"; 
		String s = "Soccer International wk43\nNational Geopgraphic (wk50)\nSchoolpaper wk39/wk43\nSome magazine week12 until 16\nAnother magazine wk36_38\nAnother magazine wk36_wk38"; 
		StringBuffer result = new StringBuffer();
		Matcher m = Pattern.compile(rx).matcher(s);
		while (m.find()) {
    		String replacement = m.group(2) == null ?
    				"week " + m.group(1):
    				"week " + m.group(1) + " - week " + m.group(2);
		    m.appendReplacement(result, replacement);
		}
		m.appendTail(result);
		System.out.println(result.toString());
 
	}
}

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