How to properly do dynamic memory allocation (C++) -

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i trying create dynamically allocated array , print it's contents in c++. although code producing incredibly strange output when print.

int main() {     int* arr;      arr = new int [1200];     memset(arr, 5, 1200);      (int = 0; < 1200; i++)         printf("%d ", arr[i]);      std::cout << '\n';     return 0; }

mixing cout , printf because playing around code. proper includes in file.\

here output:

84215045 84215045 84215045 84215045 84215045 84215045 84215045 84215045 84215045 84215045 84215045 84215045 1285 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

i have no idea how produced.

edit:

thank answers. understand code , why output looks way look.great answers.

memset(arr, 5, 1200);

if scribble whole bunch of 5'a on piece of paper , try read paper, you'll things "5555". 84215048 in hex 0x05050505.

don't manipulate arrays of data if raw chunks of memory unless know you're doing.


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