001
011
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如果能夠理解上面的部分,下面部分的代碼實現就很容易理解了。
package graycode;
import java.util.Scanner;
public class Solution {
public static String[] GrayCode(int n) {
//produce 2^n grade codes
String[] graycode = new String[(int) Math.pow(2, n)];
if(n == 1) {
graycode[0] = "0";
graycode[1] = "1";
return graycode;
}
String[] last = GrayCode(n-1);
for(int i = 0; i < last.length; i++) {
graycode[i] = "0" + last[i];
graycode[graycode.length - 1 - i] = "1" + last[i];
}
return graycode;
}
public static void main(String[] args) {
Scanner in = new Scanner(System.in);
int n = in.nextInt();
in.close();
String[] codes = new String[(int) Math.pow(2, n)];
codes = GrayCode(n);
for (String string : codes) {
System.out.println(string);
}
}
}