2019独角兽企业重金招聘Python工程师标准>>> 
https://www.codewars.com/kata/536a155256eb459b8700077e/train/java
//-- https://www.codewars.com/kata/536a155256eb459b8700077e/train/java
public class TheClockwiseSpiral{
private static final int UP = 0;
private static final int DOWN = 1;
private static final int LEFT = 2;
private static final int RIGHT = 3;
public static int[][] createSpiral(int N){
int[][] data = new int[N][N];
int toward = RIGHT;
for(int num=1,i=0,j=0; num <= N*N; num++){
data[i][j] = num;
switch(toward){
case UP:
if(i == 0 || data[i - 1][j] != 0){
toward = RIGHT;
j++;
}else{
i--;
}
break;
case DOWN:
if(i == N - 1 || data[i + 1][j] != 0){
toward = LEFT;
j--;
}else{
i++;
}
break;
case LEFT:
if(j == 0 || data[i][j - 1] != 0){
toward = UP;
i--;
}else{
j--;
}
break;
case RIGHT:
if(j == N -1 || data[i][j + 1] != 0){
toward = DOWN;
i++;
}else{
j++;
}
break;
}
}
return data;
}
}Reference:
http://bbs.csdn.net/topics/360184555