LCPC12F - Johnny The Gambler
Johnny is a gambling addict. He entered a casino and started playing a game with the dealer. The game is as follows: the dealer deals a sequence of N cards, each card containing a number C[i] and asks Johnny how many pairs (j, k) such that j < k and C[j] + C[k] = X. If Johnny answers correctly he wins, otherwise the dealer wins.
Input
The first line of input contains an integer T, the number of test cases. T test cases follow, Each test case start with the value of 0 ≤ X ≤ 2*103 followed by the number of cards 0 < N ≤ 105 followed by N numbers representing the numbers on the cards 0 ≤ C[i] ≤ 103.
Output
There should be T lines, containing the following format.
k. S
Where k is the test case number (starting at 1), a single period, a single space and S representing the number of valid pairs (j, k) as described above.
Sample
Input 1 10 3 1 5 9 Output 1. 1
hide comments
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ROHIT KUMAR:
2013-08-05 19:39:24
aftr 6 back-2-back WA---->"AC" in 0.02s:)
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chk:
2013-08-05 15:19:33
after 4 WAs finally removed from TODO list :D |
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LeppyR64:
2013-08-03 13:53:08
Confirmed Constraints: (Verified with AC C program using Assert)
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BLANKRK:
2013-07-14 04:45:03
AC...:) 1 runtym error jus due to wrong constraints........ |
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Viktor Fonic:
2013-07-04 08:34:23
Here's a test case that gave me headaches:
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Ouditchya Sinha:
2013-06-09 14:00:23
@Rajarshi Sarkar : Thank you for the insightful test case. :) |
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shiva_hellgeek:
2013-05-17 08:44:37
MY 150th problem on spoj. :) |
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Rajarshi Sarkar:
2013-04-28 10:52:52
Numbers can be same.A free test case from my side (as the description is not very clear)
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Spar!k:
2013-04-26 02:04:46
can be solved in n*logn+n |
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Eduardo Nunes:
2013-04-25 23:13:19
nice one, got 2 WAs just because I thought each number would be different ^_^ easy one with map |
Added by: | Gareev |
Date: | 2012-10-06 |
Time limit: | 1s |
Source limit: | 50000B |
Memory limit: | 1536MB |
Cluster: | Cube (Intel G860) |
Languages: | All except: ASM64 |
Resource: | LCPC 2012 |