- Time limit: 1.00 s
- Memory limit: 512 MB
There are n children who want to go to a Ferris wheel, and your task is to find a gondola for each child.
Each gondola may have one or two children in it, and in addition, the total weight in a gondola may not exceed x. You know the weight of every child.
What is the minimum number of gondolas needed for the children?
The first input line contains two integers n and x: the number of children and the maximum allowed weight.
The next line contains n integers p_1,p_2,\ldots,p_n: the weight of each child.
Print one integer: the minimum number of gondolas.
- 1 \le n \le 2 \cdot 10^5
- 1 \le x \le 10^9
- 1 \le p_i \le x
4 10 7 2 3 9