Just wondering, how high can c++ really count? Because I made a fibonacci program, and it starts acting weird and printing negatives at about 10-11 places. With both long, and int variables? Is it impossible to count higher? If not, how?
valestrom 17 Junior Poster in Training
Clinton Portis 211 Practically a Posting Shark
it can go as high as you need it to go. there is no limitation. even if hardware limitations are exceeded, ye' can still use a net based resource, which is limitless.
valestrom 17 Junior Poster in Training
it can go as high as you need it to go.
Then why does it hit negative?
Zssffssz -4 Junior Poster
I guess an array of longs might help (like a c style string) it would increase the total size Iitcould store. Wired I just asked my math teacher what the fibinatchi series was today...
Chilton 22 Junior Poster
It's based on the type of the variable. They each have their limits.
valestrom 17 Junior Poster in Training
It's based on the type of the variable. They each have their limits.
I tried both var, and long. I'm not sure what variable is higher than that.
Chilton 22 Junior Poster
You can extend your range by using unsigned integers, since your numbers aren't going to be negative.
Zssffssz -4 Junior Poster
It is compiler dependent. The C++ standard just says that Long has to be the same size or bigger than int. Same with double and float. I have also never heard of var before this.
mike_2000_17 2,669 21st Century Viking Team Colleague Featured Poster
Given the way the Fibonacci sequence works (by adding the last two values) you can pretty safely use the double type, results will not be exact (floating-point operations never are), but the range will go up to really large values (about 1.8 x 10^308).
Also, the int and long types are the same in most implementations. You'll have better luck with the uint64_t type from the <stdint.h> header. But that type will only go up to 2^64 (about 1.845 x 10^19). I think some platforms even provide uint128_t.
For higher integer numbers, you will have to use variable length integer types, which only come from special libraries, such as BigInt.
Clinton Portis 211 Practically a Posting Shark
Here is a general progression for using large numbers:
1. use a standard variable
2. use a long variable
3. use an unsigned long variable
4. split the number is several variables
5. use a c-string buffer
6. use an aggregate data type
7. use a library or dll for handling large numbers
8. upgrade hardware locally to enhance physical and/or logical memory
9. use a database or internet API
L7Sqr 227 Practically a Master Poster
Here is a general progression for using large numbers:
1. use a standard variable
What is a standard variable? I assume that you mean something smaller than a long , but there are several, so you should specify.
5. use a c-string buffer
I'd seriously caution against using a c-string as a means to calculate large numbers. An integer array, perhaps, but certainly not strings.
Although, there are libraries readily available for this type of activity. I'd skip the entire progression here and claim that there are two options:
1 - find the largest native type supported on your system ( int64_t ?)
2 - any need for something larger should be addressed immediately with a big-num library.
Clinton Portis 211 Practically a Posting Shark
short int or int for example, would be a 'standard' or most commonly used among the native c++ variables.
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