Are arrays not dynamically allocated in C++? -


this question has answer here:

i read tutorial dynamic memory in c++ , states follows:

...the size of regular array needs constant expression, , size has determined @ moment of designing program, before run...

however, ran program test this:

#include <cstdlib> #include <iostream>  using namespace std;  int main() {     int y;     cout << "enter number of elements of array: ";     cin >> y;     int x[y];   // declared array using variable size instead of constant expression     x[y-1] = 3;     cout << x[y-1];      return 0; }

...and there no errors. statement made tutorial incorrect or misinterpreting it?

no, they're not.

what you're seeing here a gnu extension called "variable length arrays" (which still stack-based).

the quotation correct in context of actual c++ language itself.

if used proper compilation flags (-wall -wextra -pedantic) your compiler tell this.


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