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[Dutchling]

Doing a Fibonacci problem.

I think it needs to be a little more efficient >.>
I've been waiting for a few minutes now and I only have 5 minutes to upload the answer ;_;

edit: negative rabbits DDDD:

[Siquo]

Poor negative rabbits... 

[Skyrunner]

Dutchling: A big hint is that you should store Fibonacci numbers you've already found in some sort of dictionary. It make it much much faster at the cost of memory.

[Dutchling]

I'll do that once i get rid of the negative rabbits

[MadocComadrin]

Dutchling: A big hint is that you should store Fibonacci numbers you've already found in some sort of dictionary. It make it much much faster at the cost of memory.

Hooray for Dynamic Programming!
(Which you should never use for the first 20 or so problems at Project Euler unless you want to really over do them.)

[Putnam]

ϕ^x-1/√5 maps really closely to the fibonacci sequence, btw.

Could be useful for something or other

[Skyrunner]

Dutchling: A big hint is that you should store Fibonacci numbers you've already found in some sort of dictionary. It make it much much faster at the cost of memory.

Hooray for Dynamic Programming!
(Which you should never use for the first 20 or so problems at Project Euler unless you want to really over do them.)

I don'tthink it's called dynamic programming.... Isn't it called optimization? Mapping Fibonacci numbers have little to do with solving a problem, just making it faster.

Also, I suspect Dutchling isn't doing Euler.. O_o

Putnam: what's ϕ?

[MagmaMcFry]

ϕ^x/√5 maps really closely to the fibonacci sequence, btw.

Fix'd the exponent (because F₀=0 and F₁=1)
Skyrunner, ϕ = (1+√5)/2, and if you want a totally exact formula (that also works for negative indices), use F_n = (ϕⁿ-(-ϕ)^-n)/√5.

[MadocComadrin]

I don'tthink it's called dynamic programming.... Isn't it called optimization? Mapping Fibonacci numbers have little to do with solving a problem, just making it faster.

http://en.wikipedia.org/wiki/Dynamic_programming

Dynamic Programming is an algorithm design paradigm for problems with overlapping subproblems and optimal substructure (that is, combining optimal solutions to subprobems creates the optimal solution for the overall problem.)

[Skyrunner]

I don'tthink it's called dynamic programming.... Isn't it called optimization? Mapping Fibonacci numbers have little to do with solving a problem, just making it faster.

http://en.wikipedia.org/wiki/Dynamic_programming

Dynamic Programming is an algorithm design paradigm for problems with overlapping subproblems and optimal substructure (that is, combining optimal solutions to subprobems creates the optimal solution for the overall problem.)

:c
That article makes me sad because I have to compete in the Seoul Informatics Olympiad and I have no idea how that works and how to solve common informatics puzzles.

Sky = doomed

[MadocComadrin]

Dutchling: A big hint is that you should store Fibonacci numbers you've already found in some sort of dictionary. It make it much much faster at the cost of memory.

Well, if understand why this works with Fibonacci numbers and can generalize it to other similar problems, you should be fine.

[dreadmullet]

I was diagnosing why something wasn't working:

Code: [Select]

const char* shaderSourceVertex = &shaderSourceVertex[0];
What. How did that even...

[Puzzlemaker]

I was diagnosing why something wasn't working:

Code: [Select]

const char* shaderSourceVertex = &shaderSourceVertex[0];
What. How did that even...

Looking at that line is like bad code inception.  There are so many levels, each more WTF then the last.  The const is what gets me, though.

[Dutchling]

[Python]

I have a problem with making a function inside a class make another instance (not sure what they are called again) of a another class.

It doesn't work if I just copy my normal code for making another class-thing with some 'self.' in front of it :v

[Mephisto]

A simple example with both classes defined in the same file.

This is Python 2, so you may need to update it for 3 if that's what you use.

Code: [Select]

class Foo:
    def __init__(self, x, y):
        self.x, self.y = x, y

    def __str__(self):
        return 'Foo instance: x=%s, y=%s' % (self.x, self.y)

class Bar:
    def __init__(self):
        self.foo = Foo(1, 2)

if __name__ == '__main__':
    b = Bar()
    print b.foo
    print b.foo.x
    print b.foo.y

Re-reading your post leads me to believe the problem may be something else. Do you have a snippet of what you did?