好久没摸过程序了，重新捡起java写了个笛卡尔乘积算法。自我感觉非常精简通用，这算是码力不减，码刀不老?
package my.table;
import java.util.Arrays;
public class Descates {
int[] sizes;
int[] indexs;
public Descates(int[] sizes) {
this.sizes = sizes;
this.indexs = new int[sizes.length];
for (int i=0; i
indexs[i] = 0;
}
}
public int[] first() {
for (int i=0; i
int index = indexs[i] ;
int size = sizes[i];
if (index < size) return indexs;
}
return null;
}
public int[] next() {
for (int i = sizes.length-1; i>=0; i--) {
int index = indexs[i] ;
int size = sizes[i];
if (index < size-1) {
indexs[i] ++;
return indexs;
}
indexs[i] = 0;
}
return null;
}
public static void main(String args[]) {
int x[] = { 2, 2, 3};
System.out.println(Arrays.toString(x));
System.out.println("===========");
Descates it = new Descates(x);
int y[] = it.first();
while (y != null) {
System.out.println(Arrays.toString(y));
y = it.next();
}
}
}
测试结果：
[2, 2, 3]
===========
[0, 0, 0]
[0, 0, 1]
[0, 0, 2]
[0, 1, 0]
[0, 1, 1]
[0, 1, 2]
[1, 0, 0]
[1, 0, 1]
[1, 0, 2]
[1, 1, 0]
[1, 1, 1]
[1, 1, 2]