/* 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) {
        Pattern p = Pattern.compile("Q(\\d+)");
        Matcher m = p.matcher("ansQaInput_Q1229_F1224");
        int counter = 0;
 
            System.out.println("group: " + m.group(1));
 
    }
}

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