思路一：做9個數組,第一個數組為1-9,從n=2開始,將上一組的每個數乘10加0-9,驗算得到的數是否是n^2的整數倍,是則存入當前數組.完成后第n個數組的長度即是所求.
思路二：直接數完9組數據,做成映射表.
1,2,3,4,5,6,7,8,9共9個
12,16,20,24,28,32,36,40,44,48,52,56,60,64,68,72,76,80,84,88,92共22個
126,162,207,243,288,324,360,369,405,441,486,522,567,603,648,684,720,729,765,801,846,882,927,963共24個
1264,2432,2880,3248,3600,3696,4416,4864,6032,6480,6848,7200,7296,8016,8464,9632,共16個
24325,28800,36000,60325,64800,72000,96325,共7個
243252,288000,360000,603252,648000,720000,963252,共7個
6480005,共1個
n＝8,9時個數為0
則建立數組a[9]={9,22,24,16,7,7,1,0,0},輸入n則直接輸出數組的第n個值即可
注意,如果數組計數從0開始,則輸入n要輸出a[n-1]