The Best Subsequence
C_K_Yang czp001 liuguangxi a_forsteri Min_25 C3PO Philippe_57721 gerrob mathpseudo sinan hervas lesnik7 Caesum dloser
Public  12/21/14  8xp  Programming  76.9% 
Consider the decimal part of PI by groups of 2 digits.
We get the following sequence for the 20 first elements:
Now group the decimal part of PI by groups of 10 digits and subtract 10^10/2 from each element.
We get the sequence:
Answer format: Sum,Starting index,Ending index
Example: 110,3,7
[My timing: 2 sec] // Computation of PI not included!
We get the following sequence for the 20 first elements:
14,15,92,65,35,89,79,32,38,46,26,43,38,32,79,50,28,84,19,71Subtract from each element of this sequence 50:
36,35,42,15,15,39,29,18,12,4,24,7,12,18,29,0,22,34,31,21You can verify that the subsequence starting at index 3 and ending at index 7 (42,15,15,39,29) has the largest sum: 110.
Now group the decimal part of PI by groups of 10 digits and subtract 10^10/2 from each element.
We get the sequence:
S = 3584073465,3979323846,2356616721,28841971,1939937510,820974944,923078164,4371379101,3628034825,1578829321, ...What is the subsequence with the largest sum in the first 5,000,000 elements of S?
Answer format: Sum,Starting index,Ending index
Example: 110,3,7
[My timing: 2 sec] // Computation of PI not included!
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