1667.Sum of Medians

Time Limit: 1s Memory Limit: 256MB

In one well-known algorithm of finding the k-th order statistics we should divide all elements into groups of five consecutive elements and find the median of each five. A median is called the middle element of a sorted array (it's the third largest element for a group of five). To increase the algorithm's performance speed on a modern video card, you should be able to find a sum of medians in each five of the array.A sum of medians of a sorted k-element set S={a1,a2,...,ak}, where a1 \lt a2 \lt a3 \lt ... \lt ak, will be understood by as 1667_1.png The 1667_2.png operator stands for taking the remainder, that is 1667_3.png stands for the remainder of dividing x by y.To organize exercise testing quickly calculating the sum of medians for a changing set was needed.

Input Format(From the terminal/stdin)

Input The first line contains number n (1 \le n \le 105), the number of operations performed.Then each of n lines contains the description of one of the three operations: add x- add the element x to the set; del x- delete the element x from the set; sum- find the sum of medians of the set. For any add x operation it is true that the element x is not included in the set directly before the operation.For any del x operation it is true that the element x is included in the set directly before the operation.All the numbers in the input are positive integers, not exceeding 109.

Output Format(To the terminal/stdout)

Output For each operation sum print on the single line the sum of medians of the current set. If the set is empty, print 0.Please, do not use the %lld specificator to read or write 64-bit integers in C++. It is preferred to use the cin, cout streams (also you may use the %I64d specificator).

Sample Input 1

Copy
6
add 4
add 5
add 1
add 2
add 3
sum
 \n
   · \n
   · \n
   · \n
   · \n
   · \n
   \n

Sample Output 1

Copy
3
 \n

Sample Input 2

Copy
14
add 1
add 7
add 2
add 5
sum
add 6
add 8
add 9
add 3
add 4
add 10
sum
del 1
sum
  \n
   · \n
   · \n
   · \n
   · \n
   \n
   · \n
   · \n
   · \n
   · \n
   · \n
   ·  \n
   \n
   · \n
   \n

Sample Output 2

Copy
5
11
13
 \n
  \n
  \n

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