Description

There are several ancient Greek texts that contain descriptions of the fabled island Atlantis. Some of these texts even include maps of parts of the island. Unfortunately, these maps describe different regions of Atlantis. Your friend Bill needs to know the total area for which maps exist. You, unwisely, volunteered to write a program that calculates this quantity.

Input

The input consists of several test cases. Each test case starts with a line containing a single integer n (1≤n≤100) of available maps. The n following lines describe one map each. Each of these lines contains four numbers: x1, y1, x2, and y2 (0≤x1<x2≤100,000 and y1<y2≤100,000), not necessarily integers. The values (x1, y1) and (x2, y2) are the coordinates of the bottom left and the top right corners, respectively, of the mapped area.

The input is terminated by a line containing a single 0. (Do not process this terminating line.)

Output

For each test case, your program should output one section. The first line of each section must be "Test case #k", where k is the number of the test case (starting with 1). The second line must be "Total explored area: a", where a is the total explored area (that is, the area covered mutually by all the rectangles in this test case), printed exact to two digits to the right of the decimal point. (Round appropriately as printf would.)

Output a blank line after each test case.

Sample Input

2
5.0 5.0 15.0 15.0
10.0 10.0 20.0 20.0
2
10 10 20 20
15 15 25 25.5
0

Sample Output

Test case #1
Total explored area: 175.00

Test case #2
Total explored area: 180.00