big int to string ( system::convert )

[ar2007]

hello,
I have to turn a big number in a string.
I tried it with sstream but the number is too large and therefore does not turn it.
I would use
but Xcode can not find the right header (stdlib.h)

  System :: convert :: toString (); 

but Xcode can not find the right header (stdlib.h)
sapreste indicarmi, qual'è l'header giusto?

thanks in advance

[ar2007]

no any help?

[Mats]

Is this not what you want?

http://www.cplusplus.com/reference/string/to_string/

[ar2007]

thx for answer mats.
to_string does not work with very big numbers.
1,xxxe^302