[algogeeks] Re: Least fare for a return trip Algorithm

2010-10-30 Thread Amod
@Harish Your understanding is correct. By reuse I meant that A(1) after being used in A(1)+ B(1) combination can be reused in A(1)+B(2) if it fulfills the criteria. Dave gave an algorithm that used A(1) once and did not include the case where where A(1) can be used in any other combination. On Oc

Re: [algogeeks] Re: Least fare for a return trip Algorithm

2010-10-29 Thread Harish U
@amod I am not sure I understand what you are saying. It is assumed that the K smallest Items(from both list A & B) are identified and arranged in increasing order as the first step. Now A(1) and B(1) constitute "the least fare" round trip(since the list is sorted) and we include that combination

[algogeeks] Re: Least fare for a return trip Algorithm

2010-10-27 Thread Amod
@Algoose Yes, but the algoritm is not correct since we are not covering the condition where element is reused. Ex ia=1 and ib=1 If we increment ia to 2 then there may be a case where A(1)+B(1) is less than A(2)+B(1) but since 1 was denoted by ia which is now 2 hence we will never be able to check t

[algogeeks] Re: Least fare for a return trip Algorithm

2010-10-17 Thread Amod
@Dave I tried to run your algorithm but I am not getting the desired results Taking inputs as given by @coolfrog AB 16 37 69 I am getting AB Sum 167 369 66 12 96 15 and the desired output would have been 1 6 7 1

Re: [algogeeks] Re: Least fare for a return trip Algorithm

2010-10-16 Thread coolfrog$
@Dave input: k=3 AB 16 37 69 output should be (1,1,7), (1,2,8), (2,1,9) im getting output form above code (1,1,7) (2,1,9) (3,1,12) Dave i am still learning algorithms .. so if i am wr

[algogeeks] Re: Least fare for a return trip Algorithm

2010-10-16 Thread Dave
@Coolfrog$: 1. No. It should be O(n + k log k) because finding the kth smallest element of an array of size n is O(n), using the Median of Medians algorithm; see http://en.wikipedia.org/wiki/Median_algorithm#Linear_general_selection_algorithm_-_Median_of_Medians_algorithm. 2. Assuming that the e

Re: [algogeeks] Re: Least fare for a return trip Algorithm

2010-10-16 Thread coolfrog$
@Dave 1. should it not be O(k + klogk) ?? 2. but u are not considering all the possible values... let k =3 like i. a1+b1 ii. min( a1+b2, a2+b1) upto these fine one of them will be chosen ...either ia or ib will increase. iii. but know we have to take remaining

[algogeeks] Re: Least fare for a return trip Algorithm

2010-10-15 Thread Dave
@Coolfrog$: You don't have to sort the arrays. You only have to find the k smallest elements in each and sort those k entries. This can be done in O(n + k log k). Algorithm: find the smallest k elements of A and sort them into ascending order. find the smallest k elements of B and sort them into a

Re: [algogeeks] Re: Least fare for a return trip Algorithm

2010-10-15 Thread coolfrog$
@amod as given A->B andB->A are in sorted form...if not sort them in O(n log n). then first suggestion A1+B1 second suggestion MIN( A1+B2 , B1+A2) ===> let it be B1+A2 third suggestion MIN( A1+B2 , A1+B3, A3+B1,A2+B3, A3+B2)> let it be A2+B3 and so on... @Dave what

[algogeeks] Re: Least fare for a return trip Algorithm

2010-10-13 Thread Amod
@Dave You are partly correct. If i ask for four minimum fares for the round trip then first suggestion is what u said : sum the sum of the minimum cost from A to B and the minimum cost from B to A after that we have to see which combination from both costs, sums up least On Oct 14, 9:55 am, Dave

[algogeeks] Re: Least fare for a return trip Algorithm

2010-10-13 Thread Dave
@Amod. Isn't the minimum sum the sum of the minimum cost from A to B and the minimum cost from B to A? What am I missing? Dave On Oct 13, 11:06 pm, Amod wrote: > Hi > > I think I forgot to mention that the SUM of the ROUND trip i.e. A->B->A  (sum > = going + returning) should be least. > > Plea

[algogeeks] Re: Least fare for a return trip Algorithm

2010-10-13 Thread Amod
Hi I think I forgot to mention that the SUM of the ROUND trip i.e. A->B- >A (sum = going + returning) should be least. Please don't take into account any other thing like time and availability. So solution is not that straightforward. Its like we have two arrays and we have to return least k sum

Re: [algogeeks] Re: Least fare for a return trip Algorithm

2010-10-13 Thread AlgoSau Sau
Although no inputs are given on flight timing (date and time) front but that is one more factor that should be considered while scheduling the cheapest round trip journey as it happens on travel sites normally On Wed, Oct 13, 2010 at 2:56 PM, Shiyam code_for_life < mailshyamh...@gmail.com> wrote:

[algogeeks] Re: Least fare for a return trip Algorithm

2010-10-13 Thread Shiyam code_for_life
When a user wants to choose to fly from A to B, suggest the flight with lowest fare that's available, here its A1, if A1 is busy then A2 and so on Repeat the same for B to A. Am I missing something here? Complexity is O( (number of flights from A to B) + number of flights from B to A) ) Cheers

[algogeeks] Re: Least fare for a return trip Algorithm

2010-10-12 Thread Amod
Could you please elaborate on O(n+m) algorithm that you have used On Oct 12, 6:43 pm, ligerdave wrote: > sorting is absolutely required. w/o the sorting, how are you going to > find the min? comparison is also a sorting algorithm. > it also depends on how many suggestions you wanna have. if it's

[algogeeks] Re: Least fare for a return trip Algorithm

2010-10-12 Thread ligerdave
sorting is absolutely required. w/o the sorting, how are you going to find the min? comparison is also a sorting algorithm. it also depends on how many suggestions you wanna have. if it's just the best deal, you can complete this in O(n+m) where n is the number of different fares of trip to and m i