String to Integer array

Question

Hey
I needed some help.
How do I convert the string into an integer array in C++ ?
I'm taking the string from command line .
Edit : After conversion I'm facing problem with the array storage.

I've used a for(i=0;str.length();i++) to display the integer array since arr where the array is stored won't have length / size function.

Answer 1

atoi() convert a char array to int
int x=0;
this is how to convert it manually
string str="543;
for(int i=0;i<str.length();i++)
{
x*=10;
x+=str[i]-'0';
}

Answer 2

~ swim ~ yes it's a number string in the form of '1 2 3 4' . Thank you .