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Alboin wrote:Use GMP.

Zacariaz wrote:

Alboin wrote:Use GMP.

all i need is to be able to asign a exstremely large value to a variable so i can pass it around, is that really so hard?

Next: Assigning Integers, Previous: Integer Functions, Up: Integer Functions
5.1 Initialization Functions

The functions for integer arithmetic assume that all integer objects are initialized. You do that by calling the function mpz_init. For example,
{
mpz_t integ;
mpz_init (integ);
...
mpz_add (integ, ...);
...
mpz_sub (integ, ...);

/* Unless the program is about to exit, do ... */
mpz_clear (integ);
}

As you can see, you can store new values any number of times, once an object is initialized.
— Function: void mpz_init (mpz_t integer)

Initialize integer, and set its value to 0.
— Function: void mpz_init2 (mpz_t integer, unsigned long n)

Initialize integer, with space for n bits, and set its value to 0.

n is only the initial space, integer will grow automatically in the normal way, if necessary, for subsequent values stored. mpz_init2 makes it possible to avoid such reallocations if a maximum size is known in advance.
— Function: void mpz_clear (mpz_t integer)

Free the space occupied by integer. Call this function for all mpz_t variables when you are done with them.
— Function: void mpz_realloc2 (mpz_t integer, unsigned long n)

Change the space allocated for integer to n bits. The value in integer is preserved if it fits, or is set to 0 if not.

This function can be used to increase the space for a variable in order to avoid repeated automatic reallocations, or to decrease it to give memory back to the heap.

Zacariaz wrote:The linked list aproach was allso my first thought but its not where the prolem lies i think.

The problem is that i dont know how to assign a value to my specialized datatype in the first place.

mydatatype variable = somebiginteger // my compiler will never accept this, at least not with any aproach i know of.

class mydatatype {
public:
    mydatatype(const somebigintegertype &val) { ...; valuecount = sizeof(somebigintegertype) / sizeof(unsigned long); }
    mydatatype() { valuecount = 0; }
    const mydatatype &operator=(const mydatatype &rhs) { ... }
private:
    unsigned long *value;
    unsigned int valuecount;
};

Zacariaz wrote:ther than possible as a string, however that would not be the most ideal way i think.

Zacariaz wrote:sprry, but i dont understand.
SomeBigIntetegerType is exactly what im missing.
Then problem is that i have no way to pass the value to mydatatype in the first place, other than possible as a string, however that would not be the most ideal way i think.
I glad you made the effort but if i am to use your advice, you have to explain further.

And by the way, i do use a C++ compiler.

Thanks

Candy wrote:What are you going to use such numbers for though?