Description

The problem is as follows: given some expressions composed of $\sin^2 x$ and $\cos^2 x$ with $x=\dfrac{\pi}{7}$, please find the maximum integer value you can obtain by selecting some of the expressions and summing them.

Input Format

The first line contains an integer $n$, indicating $n$ expressions.

Each of the next $n$ lines contains a string formed by $f(i)=\sin^2 x$, $\cos^2 x$ and plus signs, with $x=\dfrac{\pi}{7}$.

To simplify the input, we use s to represent $\sin^2 x$, c to represent $\cos^2 x$, and omit f(i)=.

Output Format

Output a single number representing the maximum integer answer. All operations are addition.

3
s+c
s+c+s
c

3

Hint

Sample Explanation:

• If you pick all three expressions, their sum equals $3$.

Constraints:

• Let the total count of s and c be $m$.
• For $10\%$ of the testdata, $n=1$.
• For another $20\%$ of the testdata, each line is a single-term expression.
• For another $20\%$ of the testdata, $n \le 20$.
• For $100\%$ of the testdata, $n \times m \le 5 \times 10^7$, $m \le 10^6$.

Tips:

• $\forall x,\ \sin^2 x + \cos^2 x = 1$.

Translated by ChatGPT 5