Segments

Time Limit: 2 Seconds
Memory Limit: 65536 KB

Given *n* segments in the two dimensional space, write a program, which determines if there exists a line such that after projecting these segments on it, all projected segments have at least one point in common.

**Input**

Input begins with a number *T* showing the number of test cases and then, *T* test cases follow. Each test case begins with a line containing a positive integer *n* <= 100 showing the number of segments. After that, *n* lines containing four real numbers *x1 y1 x2 y2* follow, in which (*x1*, *y1*) and (*x2*, *y2*) are the coordinates of the two endpoints for one of the segments.

**Output**

For each test case, your program must output "Yes!", if a line with desired property exists and must output "No!" otherwise.

**Sample Input**

3

2

1.0 2.0 3.0 4.0

4.0 5.0 6.0 7.0

3

0.0 0.0 0.0 1.0

0.0 1.0 0.0 2.0

1.0 1.0 2.0 1.0

3

0.0 0.0 0.0 1.0

0.0 2.0 0.0 3.0

1.0 1.0 2.0 1.0

**Sample Output**

Yes!

Yes!

No!

Author:

**Babak Behsaz**
Source:

**AUT Contest 1**
Submit
Status