该题面有部分缺失。

题目描述应添加：

Moreover group shouldn't change their relative position while taken their seats in class room i.e. group $3$ take their seat if and only if group $1$ and $2$ took their seats.

Find size $x$ of class room and number of class room y such that there is no empty seats in class room (i.e. the total number of student present inside the class room is equal to $x$)?

Moreover group shouldn't change their relative position while taken their seats in class room i.e. group $3$ take their seat if and only if group $1$ and $2$ took their seats.

Find size $x$ of class room and number of class room y such that there is no empty seats in class room (i.e. the total number of student present inside the class room is equal to $x$)?

输入描述应添加：

The first line contains an integer ($1 \le n \le 10^5$). The second line contains $n$ space-separated integers $a_0, a_1, ... a_{n-1}$ ($1 \le a_i \le 10^4$).

The first line contains an integer ($1 \le n \le 10^5$). The second line contains $n$ space-separated integers $a_0, a_1, ... a_{n-1}$ ($1 \le a_i \le 10^4$).

翻译应该增加条件：每个队伍应该按顺序就座，即第3组在第1组和第2组就座时才就座。