LAZYPROG - The lazy programmer

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A new web-design studio, called SMART (Simply Masters of ART), employs two people. The first one is a web-designer and an executive director at the same time. The second one is a programmer. The director is so a nimble guy that the studio has already got N contracts for web site development. Each contract has a deadline di.

It is known that the programmer is lazy. Usually he does not work as fast as he could. Therefore, under normal conditions the programmer needs bi of time to perform the contract number i. Fortunately, the guy is very greedy for money. If the director pays him xi dollars extra, he needs only (bi - ai*xi) of time to do his job. But this extra payment does not influence other contracts. This means that each contract should be paid separately to be done faster. The programmer is so greedy that he can do his job almost instantly if the extra payment is (bi/ai) dollars for the contract number i.

The director has a difficult problem to solve. He needs to organize programmer’s job and, may be, assign extra payments for some of the contracts so that all contracts are performed in time. Obviously he wishes to minimize the sum of extra payments. Help the director!


First line of the input contains an integer t (1t45), equal to the number of testcases. Then descriptions of t testcases follow.

First line of description contains the number of contracts N (1N100000, integer). Each of the next N lines describes one contract and contains integer numbers ai, bi, di (1ai, bi10000; 1di1000000000) separated by spaces.

At least 90% of testcases will have 1N10000.


For each testcase in the input your program should output one line with a single real number S. Here S is the minimum sum of money which the director needs to pay extra so that the programmer could perform all contracts in time. The number must have two digits after the decimal point.


20 50 100
10 100 50


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Vipul Srivastava: 2017-03-11 14:02:24

Very nice question

Amit Jaiswal: 2015-07-06 11:24:25

Thnx for d hint ravi kiran..yup priority queue works.. :-)

Zombies: 2013-06-25 07:35:57

I m still getting WA .Please check admin..
Here is my solution

Edit : Got the Problem (final printf with "%Lg" was not working but with "%Lf" did the job ) :D :D

Last edit: 2013-06-28 12:05:42
Shubham.IIITM: 2012-07-03 12:36:27

gettng TLE...

pls help :(

Cena: 2011-12-24 12:48:04

plz another test case this one is so trivial :/

Ravi Kiran: 2010-05-24 16:08:00

Phew Tough Problem!!Not as easy as it seems.
Comments after solving:
1.)I got ac using only double for arithmetic wherever decimal was required.
2.)I used a priority_queue during processing.
Hope this helps. :-)

:D: 2010-02-23 06:51:51

Use high precision floating point numbers (like long double) to avoid accuracy issues

Added by:Ivan Metelsky
Time limit:1.491s
Source limit:50000B
Memory limit:1536MB
Cluster: Cube (Intel G860)
Languages:All except: NODEJS PERL6 VB.NET
Resource:NEERC Western Subregion QF 2004