Uh oh, the weather forecast predicts that a rainstorm will soon break out over the infinite, 1-dimensional number line you call home!
The forecast is remarkably precise. In fact, it's known that exactly N raindrops will fall, with the ith drop striking the number line at position Xi exactly Ki seconds after the start of the storm. No two drops will strike the number line at exactly the same position and time.
You'd like to stop as many of the drops as possible, but you don't exactly have an umbrella... so your boomerang will have to do. Your plan is as follows:
During the inclusive time interval from when you throw the boomerang to when you catch it again, if the boomerang is ever at exactly the same position as a raindrop at exactly the time that it strikes the number line, it will intercept it... just like an umbrella! What's the maximum number of raindrops you can intercept in this way with a single throw?
Input begins with an integer T, the number of rainstorms. For each rainstorm, there is first a line containing the space-separated integers N and S. Then, N lines follow, the ith of which contains the space-separated integers Xi and Ki.
For the ith rainstorm, print a line containing "Case #i: " followed by the maximum number of raindrops you can stop.
1 ≤ T ≤ 50
1 ≤ N ≤ 100,000
1 ≤ S ≤ 1,000,000,000
0 ≤ Xi, Ki ≤ 1,000,000,000
In the first rainstorm, one solution is to stand at X = 99 and let your boomerang spin at X = 100 until it intercepts all three raindrops that will fall at that position. In the second rainstorm, one solution is to stand at X = 50 and throw your boomerang towards X = 100 as soon as the first raindrop hits it. If you recall your boomerang as soon as it reaches X = 100, it will hit the second raindrop and be back just in time to hit the third.