public static void main(String[] args){
              int number = 12345;
             
              int temp = number;            
              int count = 0;
              while(number !=  0){               
              number  =  number / 10;
              //System.out.println(number);
              count++;
              }
              //System.out.println(count);
             
              //动态 静态    因为不知道元素是什么，所以需要动态初始化
              int []arr = new int [count];
            
              //System.out.println(temp);
              int index = arr.length -1;
              while(temp != 0){//12345
                
                  int ge = temp % 10;
                
                  temp = temp / 10;
              
                  arr[index] = ge;
                  index--;
              }
                1 2 3 4 5
              for(int i =0;i < arr.length;i++){
                System.out.print(arr[i] + " ");
              }