import java.util.*;
import java.lang.*;
import java.io.*;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
 
/* 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 regex = "\\[([0-9]+)\\]$";
		String string = "[52,52,73,52],[23,32],[40]";
		Pattern pattern = Pattern.compile(regex);
		Matcher matcher = pattern.matcher(string);
		if(matcher.find()) {
			System.out.println(matcher.group(1)); // 40
		}
	}
}

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