/* 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 = "\n";
		System.out.println(s.replaceAll("\n", "LF")); 
		System.out.println(s.replaceAll("\\n", "LF")); 
		System.out.println(s.replaceAll("(?x)\\n", "LF"));
		System.out.println(s.replaceAll("(?x)\\\n", "LF")); 
		System.out.println(s.replaceAll("(?x)\n", "<LF>")); 
	}
}

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