Dynamic Array Size in C++ -

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i looking way dynamically set size of integer array depending on passed parameter. example in pseudocode:

int myfunction(int number) {   int myarr[amount of digits in number]; }

so when input 13456 int array[] size should 5. whats quickest way in c++, when don't know constant size?

you cannot create array run-time size, must known @ compile time. recommend std::vector instead.

one solution count characters after converting string

#include <string> int myfunction(int number) {     std::vector<int> myarr(std::to_string(number).size()); }

mathematically, can take log (base 10) find number of digits in number. 

#include <cmath> int myfunction(int number) {     int numdigits = static_cast<int>(std::log10(number)) + 1;     std::vector<int> myarr(numdigits); }

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