Drinks

Source: Codeforces

Version: Phuoc Hung OJ Extended

Problem Statement

There are $n$ drinks. The volume percentage of orange juice in drink $i$ is $p_i$. Equal amounts are taken from all $n$ drinks and mixed together.

Compute the percentage of orange juice in the resulting mixture.

Input

• The first line contains an integer $n$, the number of drinks.
• The second line contains $n$ integers $p_0,p_1,\ldots,p_{n-1}$, where $p_i$ is the orange-juice percentage of drink $i$.

Output

Print the orange-juice percentage of the mixture as a real number. The answer is accepted if its absolute or relative error does not exceed $10^{-4}$.

Subtasks

Subtask 1 (100 points): $1\le n\le100$ and $0\le p_i\le100$.

Examples

Input

3
50 50 100

Output

66.666666666667

Explanation

The three percentages are $50\%$, $50\%$, and $100\%$. Their equal-weight average is

$$\frac{50+50+100}{3}=\frac{200}{3}\approx66.666666666667.$$