Problems

# Cannon

At the origin guns and shooting balls of ping-pong.At some distance Rfrom it, parallel to the axisОХ, is a brick wall of infinite length. Between the wall and the axisOXis objective point with coordinates (X,Y). Required to target the gun so that the ball hit his first against the wall, then hit the target. Determine the shortest distance from the axisOYto the point of collision of the ball with the wall.

Input

The first line of the input file contains a number of tests. For each test on a separate line contains three integers,R, X and Y (-10<=X<=10, 0<=Y<R<=10), separated by spaces.

Output

For each test in a separate line shows the distance in a straight line from the axis OYto the point of impact of the ball against the wall up to two decimal places.

Time limit 1 second
Memory limit 64 MiB
Input example #1
2
10 5 5
10 10 5

Output example #1
3.33
6.67

Source Школа Программиста, Красноярский край, Пятая командная олимпиада, 15 ноября 2009, Задача F