Please help me to solve this problem, if so, LiangChen must have zhongxie!
There is a sequence contains n integers a0, a1, ...., an, firstly all of them equal 0,
and there are q opertions, each of them either is
0 x; add ax by 1
or
1 l r; calculator the total number of ai that ai mod 3 == 0 (l <= i <= r)
For each test case, first line contains "Case X:", then print your answer, one line contains one integer.