Quadratic Function

Problem Description

Compute the extremum (minimum or maximum) of the quadratic function $f(x) = ax^2 + bx + c$.

Input Format

The first line contains an integer $test$, the number of test cases.

The next $test$ lines each contain three integers $a, b, c$.

Output Format

Output $test$ lines in total, each giving the answer for one test case. A relative or absolute error within $10^{-9}$ is accepted.

Sample Input

1
1 2 1

Sample Output

0.0000000000

Constraints

For $100\%$ of the data: $1 \leq test \leq 10000$, $1 \leq a \leq 1000$, $-1000 \le b, c \le 1000$.