# Tridiag

New York is a truly magical city. You can feel at home no matter where youâ€™re from. Whether youâ€™re a subway person or a taxi person, a day person or a night person, rich or poor, NYC is bound to scratch every itch that you have. NYC is a melting pot of cultures. You can visit China, Korea, Mexico, and Italy every day of the year without having to plan an outrageously expensive trip. NY combines the old and thenew. Check out those amazing street artists in front of the Metropolitan Opera House if youâ€™re in for a combo of Mussorgsky and Metallica. So... if youâ€™re ever here for a visit, pick up a brochure and work your way through the city. Ohh... and on your way, you might just find yourself a puzzle...like this one... Solve the following system:

## Input

On the first line of the input there is N
Each of the following N lines contains 4 integers: Ai Bi Ci Di.

## Output

Line i of the input contains xi.

## Constraints

`1 ≤ N ≤ 100 000`
`-100 ≤ Ai Bi Ci Di ≤ 100`
`Bi != 0`
The output result is considered correct if and only if the diference between your result and the correct one is less then or equal to 1e-7.

InputOutput
5
-1 2 -1 1
-1 2 -1 0
-1 2 -1 0
-1 2 -1 0
-1 2 -1 1
1.00000000
1.00000000
1.00000000
1.00000000
1.00000000
Questions?