import java.util.*;
import java.lang.*;
import java.io.*;
 
/* 
 * Bug demonstration
 * Static code analyzer AppСhecker: cnpo.ru/en/solutions/appchecker.php
*/
class AppCheckerStringBuilder
{
	public static void main (String[] args) throws java.lang.Exception
	{
		StringBuilder sb = new StringBuilder('[');
 
		sb.append('a');
		sb.append(' ');
		sb.append('b');
 
		sb.append(']');
 
		System.out.println("Expected: [a b]");
		System.out.println("Real: " + sb.toString());
	}
}

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