Hey all, been a while, this is where I'm at now
Mostly done with Ruby, some done in Java, some in C, one in Assembly (it's great for brute forcing!)
Taking C++ and stats next semester, hopefully those will go well.
(131/226)
001, 002, 003, 004, 005, 006, 007, 008, 009, 010,
011, 012, 013, 014, 015, 016, 017, 018, 019, 020,
021, 022, 023, 024, 025, 026, 027, 028, 029, 030,
031, 032, 033, 034, 035, 036, 037, 038, 039, 040,
041, 042, 043, 044, 045, 046, 047, 048, 049, 050,
051, 052, 053, 054, 055, 056, 057, 058, 059, 060,
061, 062, 063, 064, 065, 066, 067, 068, 069, 070,
071, 072, 073, 074, 075, 076, 077, 078, 079, 080,
081, 082, 083, 084, 085, 086, 087, 088, 089, 090,
091, 092, 093, 094, 095, 096, 097, 098, 099, 100,
101, 102, 103, 104, 105, 106, 107, 108, 109, 110,
111, 112, 113, 114, 115, 116, 117, 118, 119, 120,
121, 122, 123, 124, 125, 126, 127, 128, 129, 130,
131, 132, 133, 134, 135, 136, 137, 138, 139, 140,
141, 142, 143, 144, 145, 146, 147, 148, 149, 150,
151, 152, 153, 154, 155, 156, 157, 158, 159, 160,
161, 162, 163, 164, 165, 166, 167, 168, 169, 170,
171, 172, 173, 174, 175, 176, 177, 178, 179, 180,
181, 182, 183, 184, 185, 186, 187, 188, 189, 190,
191, 192, 193, 194, 195, 196, 197, 198, 199, 200,
201, 202, 203, 204, 205, 206, 207, 208, 209, 210
211, 212, 213, 214, 215, 216, 217, 218, 219, 220
221, 222, 223, 224, 225, 226
What a coincidence, I also solved 131 problems. unfortunately I'm kinda stuck at this point.
(131/226)
001, 002, 003, 004, 005, 006, 007, 008, 009, 010,
011, 012, 013, 014, 015, 016, 017, 018, 019, 020,
021, 022, 023, 024, 025, 026, 027, 028, 029, 030,
031, 032, 033, 034, 035, 036, 037, 038, 039, 040,
041, 042, 043, 044, 045, 046, 047, 048, 049, 050,
051, 052, 053, 054, 055, 056, 057, 058, 059, 060,
061, 062, 063, 064, 065, 066, 067, 068, 069, 070,
071, 072, 073, 074, 075, 076, 077, 078, 079, 080,
081, 082, 083, 084, 085, 086, 087, 088, 089, 090,
091, 092, 093, 094, 095, 096, 097, 098, 099, 100,
101, 102, 103, 104, 105, 106, 107, 108, 109, 110,
111, 112, 113, 114, 115, 116, 117, 118, 119, 120,
121, 122, 123, 124, 125, 126, 127, 128, 129, 130,
131, 132, 133, 134, 135, 136, 137, 138, 139, 140,
141, 142, 143, 144, 145, 146, 147, 148, 149, 150,
151, 152, 153, 154, 155, 156, 157, 158, 159, 160,
161, 162, 163, 164, 165, 166, 167, 168, 169, 170,
171, 172, 173, 174, 175, 176, 177, 178, 179, 180,
181, 182, 183, 184, 185, 186, 187, 188, 189, 190,
191, 192, 193, 194, 195, 196, 197, 198, 199, 200,
201, 202, 203, 204, 205, 206, 207, 208, 209, 210
211, 212, 213, 214, 215, 216, 217, 218, 219, 220
221, 222, 223, 224, 225, 226
Yeah, they definitely get harder :/
The ones I find most rewarding are ones where I can brute force the low solutions, evaluate them and find a pattern to get the higher ones. But now that I've learned dynamic programming, I also enjoy ones that I can solve using this. Sometimes I get tired of working on a problem, brute force it with some long algorithm, then go to look at the solution, and seeing how it was done, wish I would have worked on it more :/
Other times, though, I look at it and am glad I brute forced it ^_^
I have a few problems that I'm saving for when I get into the C++ course, I also really enjoy the problems where I get to deal with graphs.
I made an algorithm to solve problem 13 and this is my answer:
3737623039
If any one can tell me the right answer because when i type this number in the site it gives me a wrong answer ,and i don't know what's wrong with my program....
I don't think so. Everyone has help, whoever has taken a math course has learned something they can use in PE, I learned about La Grange multipliers in school the same week I tried problem 190, should I have put that knowledge out of my head because it came from an outside source and helped me with the Project Euler problem? Or is it intentionality that makes the difference? If we are lucky enough to learn the solution unintentionally it is valid, but if we intentionally learn it, it is not? (Then again, I intentionally took the course) The home page says you can research problems, Mathworld, Wikipedia, and a textbook surely contain many times more information than asking for aid.
The home page says the problems are aimed at students, and adults whose background is not primarily mathematics, so one isn't expected to have Euler's capabilities in order to participate in Project Euler (though one could certainly argue that they deviate from this in the later problems).
It says the motivation for starting and continuing PE is "to provide a platform for the inquiring mind to delve into unfamiliar areas and learn new concepts in a fun and recreational context" , and guidance is one of the most effective forms of learning (hence school). Also, it is not fun and recreational to try a problem fifty times with no correct answer and no feedback on where you are going wrong, this is essentially why I quit working on spoj.pl, while I made it all the way through javabat.com, learned a lot along the way, and was hungry for more.
I think the spirit of PE is that each person get from it what that person wants from it, and for many of us, guidance makes a problem much less frustrating and much more interesting and rewarding.
Which is obviously not what he did.
How can i handle large integers ?
In problem 25 he want's the following:
What is the first term in the Fibonacci sequence to contain 1000 digits?
I thought of it and developed an algorithm to solve it using an arrays but it seems to be inefficient if any one can tell me how to handle large integers ...
1000 digits !!!
Look at Binet's formula for the n-th Fibonacci number. It is the sum of two terms one of which growns with increasing n and the other goes to zero as n increases.
Use the log_10 of just the increasing term to estimate the number of digits of F_n for large n.
No need for extended prescision etc.
CB