题目描述
There are N boxes arranged in a row.
Initially, the i-th box from the left contains a_i candies.
Snuke can perform the following operation any number of times:
- Choose a box containing at least one candy, and eat one of the candies in the chosen box.
His objective is as follows:
- Any two neighboring boxes contain at most x candies in total.
Find the minimum number of operations required to achieve the objective.
-----Constraints-----
- 2 ≤ N ≤ 10^5
- 0 ≤ a_i ≤ 10^9
- 0 ≤ x ≤ 10^9
-----Input-----
The input is given from Standard Input in the following format:
N x
a_1 a_2 ... a_N
-----Output-----
Print the minimum number of operations required to achieve the objective.
-----Sample Input-----
3 3
2 2 2
-----Sample Output-----
1
Eat one candy in the second box.
Then, the number of candies in each box becomes (2, 1, 2).
输入格式
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输出格式
见题面