import java.util.regex.Matcher;
import java.util.regex.Pattern;
 
class Main {
        public static void main (String[] args) throws java.lang.Exception {
        String s1 = "dev_mount flash /mnt/sdcard auto /devices/virtual/mtd/mtd9/mtdblock9";
        String regex = "^[^#]*(mnt/[_a-z]*)";
        Pattern pattern = Pattern.compile(regex);
        Matcher m = pattern.matcher(s1);
        if (m.find()) {
            System.out.println(m.group(0));
            System.out.println(m.group(1));
        }
    }
}

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