StrinbBuffer sb = new StringBuffer();
for (int i = 0; i < n; i++) {
sb.append(0);
}
String s1 = Integer.toBinaryString(10진수); //2진수 변환
String s2 = Integer.toBinaryString(10진수);
DecimalFormat df = new DecimalFormat(sb.toString()); //자리수에 맞게 패딩
String s1Format = df.format(Integer.parseInt(s1));
String s2Format = df.format(Integer.parseInt(s2));