Question: Is it possible to define `999e999` value without using the `char` type?

I've tried defining it even with `unsigned long long`, but the compiler keeps giving me `constant too big` error.

Thanks in advance.

Answer: 
> 
> Is it possible to define `999e999` value without using the char type?
> 
> 
> 

No, that's not possible using intrinsic c++ data types. That's a way to big number that could be held in either a `unsigned long long` type in c++.

A `long double` type would enable you to use 10 based exponents as large as you want, for modern FPU architectures.

What can be achieved with your current CPU architecture can be explored using the [`std::numeric_limits`](https://en.cppreference.com/w/cpp/types/numeric_limits) facilities like this:

```
#include <iostream>
#include <limits>

int main() {   
   std::cout<< "max_exponent10: " << std::numeric_limits<long double>::max_exponent10  << std::endl;
}

```

Output:

```
max_exponent10: 4932

```

See the [online demo](http://coliru.stacked-crooked.com/a/652a1733413070aa)

You have to use a 3rd party library (like [GMP](https://gmplib.org/)) or write your own algorithms to deal with big numbers like that.
In most (If not all) implementations, that constant is just too big to be represented as a `unsigned long long` or `long double` (Though some may just have it be floating point infinity).

You may instead be interested in [`std::numeric_limits<T>::infinity()`](https://en.cppreference.com/w/cpp/types/numeric_limits/infinity) (for `float`, `double` or `long double`) or [`std::numeric_limits<T>::max()`](https://en.cppreference.com/w/cpp/types/numeric_limits/max) instead.