P1687 Robot Xiao Q

After successfully delivering a big order, the restaurant decided to bring in a new member: Robot Xiao Q. Xiao Q’s arrival brought in many more customers, but after a while a new problem appeared. Unlike us, Xiao Q needs energy input to keep going. The energy menu already lists $N$ units of energy in a fixed order, but because their sources differ, ingesting each unit takes a certain amount of time. Xiao Q’s maximum charging time per day is $119$; if this limit is exceeded, he will crash automatically. Everyone wants Xiao Q to stay, so after some research, HWX and XYF went to negotiate with the boss. From LXC’s point of view, he does not want to hear any sob story; he only wants to know: to let Xiao Q obtain $K$ units of energy (that is, you may skip some units on the menu), what is the minimum number of days needed for charging?

The first line contains two integers $N, K$, meaning there are $N$ energy units on Xiao Q’s menu, and we want to obtain $K$ of them. The second line contains $N$ integers, where the $i$‑th integer is the charging time required for the $i$‑th energy unit.

Output a single line containing one integer: the minimum number of days required. If it is impossible to meet the requirement, output `You can't do it.`.

### Sample Explanation Accept only $1,1,118$. Obviously, this takes $2$ days. ### Constraints For $30\%$ of the testdata, $1 \le K \le N \le 20$. For $100\%$ of the testdata, $1 \le K \le N \le 3000$. Translated by ChatGPT 5