C. Trash Removal
time limit per test
1 second
memory limit per test
256 megabytes
input
standard input
output
standard output

Bob is walking in his neighborhood park, when he suddenly sees $$$N$$$ piles of trash! Being a conscientious citizen, Bob wants to clean up his environment.

Each pile of trash has a weight of $$$a_i$$$ ($$$1 \lt = i \lt = N$$$) pounds. Bob throws the trash away by making trips to the trash can. However, Bob can carry at most $$$K$$$ pounds of trash in one trip. Help Bob determine the minimum number of trips he must make to dispose of all piles of trash!

Bob must begin picking up trash from the first pile, then the second, and so on. It is guaranteed that for all $$$i$$$ that $$$a_i \lt = K$$$.

Input

Line $$$1$$$: Two space separated integers $$$N$$$ ($$$1 \le N \le 10^5$$$) and $$$K$$$ ($$$1 \le K \le 10^5$$$).

Line $$$2$$$: $$$N$$$ space separated integers: $$$a_1, a_2, … a_N$$$ ($$$1 \le a_i \le K$$$), each representing the weight of the $$$i$$$th pile of trash.

Output

Line $$$1$$$: One integer representing the minimum number of trips to get rid of all the trash.

Example
Input
3 2
1 1 2
Output
2