05 hex conversion

1 Binary Coded Decimal

public class 二进制转十进制 {
	public static void main(String[] args) {
		System.out.println(bin2Oct("110011"));
	}

	private static double bin2Oct(String str) {
		char[] cs = str.toCharArray();
		double sum = 0;
		for (int i = 0; i < cs.length; i++) {
			sum = sum + (cs[i] - 48) * Math.pow(2, cs.length - i - 1);
		}
		return sum;
	}
}

2 decimal binary transfer

public class 十进制转二进制 {

	public static void main(String[] args) {
		System.out.println(convert(8,2));
	}

	static String convert(int source, int jinzhi) {
		int beichushu = source;

		StringBuffer sb = new StringBuffer(8);

		int shang = 0;
		int chushu = jinzhi;
		int yushu = 0;
		do {
			shang = beichushu / chushu;
			yushu = beichushu % chushu;
			sb.insert(0, yushu);
			if (shang == 0) {
				break;
			}
			beichushu = shang;
		} while (true);
		return sb.toString();
	}
}