- Time limit: 1.00 s
- Memory limit: 512 MB
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.
- $1 \le n \le 2 \cdot 10^5$
- $1 \le x \le 10^9$
- $1 \le p_i \le x$
7 2 3 9