The provided code stub will read in a dictionary containing key/value pairs of name:[marks] for a list of students. Print the average of the marks array for the student name provided, showing 2 places after the decimal.

Example

$\textbf{marks key:value pairs are}$

$\text{'alpha'}:[20,30,40]$

$\text{'beta'}:[30,50,70]$

$\textbf{query_name}=\textbf{'beta'}$

The query_name is 'beta'. beta's average score is $(30+50+70)/3=50.0$.

Input Format

The first line contains the integer $n$, the number of students' records. The next $n$ lines contain the names and marks obtained by a student, each value separated by a space. The final line contains query_name, the name of a student to query.

Constraints

$2\leq n\leq10$
$0\leq\textit{marks}[i]\leq100$
$\textbf{length of marks arrays}=3$

Output Format

Print one line: The average of the marks obtained by the particular student correct to 2 decimal places.

Sample Input 0
3
Krishna 67 68 69
Arjun 70 98 63
Malika 52 56 60
Malika

Sample Output 0
56.00

Explanation 0

Marks for Malika are $\{52,56,60\}$ whose average is $\frac{52+56+60}{3}\Rightarrow56$

Sample Input 1
2
Harsh 25 26.5 28
Anurag 26 28 30
Harsh

Sample Output 1
26.50

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