Thread: Can a string be converted to an array of characters?

Can you break and store a string up into an array of characters?

What if the string is dynamic?

Code:

char *buf;
string mystring = "Hello World, I have no clue how long this is!";

buf = new char[mystring.length() + 1];
strcpy(buf, mystring.c_str());

Like that maybe?

I've tried to do this but I don't know where I am going wrong. Basically I am trying to read two lines of characters from an input file. The input file is called in like this: a.out < inputfile
For those of you who are not familar with this, this just mean you are feeding it through a file rather than through the keyboard. So

Code:

int some_value;
cin << some_value

will just make the program read the first integer and so forth.... My problem is this: I cannot read in the two character arrays successfully. The contents of the sample input file is as follows:

Code:

ABSDEF
SDEFEA

I need to read the first line into the first character array and the second line into the second character array. Please please help.

Great! That worked. Now I just need to get the length of one of the arrays. It could be either one since both have the same length.

Thanks to everyone on this post I have this much to read in from the input file to the corresponding arrays. I do have one problem though and that is how to get the length of each of the arrays. The way that I have tried below is to use Waldo2K2's code(thank you). I made two arrays and now want to travel through them until I reach a delimiter, in this case, '\n'. Seems logical enough but its just not working.

Code:

int main(){
  char preorder[26];
  char inorder[26];

  // store values from input file into arrays
  cin.getline(preorder, '\n');
  cin.getline(inorder, '\n');


  // WHY DOESN'T THIS BLOCK OF CODE WORK TO TRAVERSE AND
  // FIND THE LENGTH OF the array(s)??
  int i = 0;
  int length = 0;
  while (preorder[i] != '\n'){
    length++;
    i++;
  }

  cout << "length: " << length << "\n";

  cout << "preorder = ";
  for (int i = 0; i < 6; i++){
    cout << preorder[i];
  }

  cout << "\n";

  cout << "inorder = ";
  for (int i = 0; i < 6; i++){
    cout << inorder[i];
  }
  cout << "\n";

  return 0;
}

When you read in a line

Code:

 cin.getline(preorder, '\n');

you read in until but not including the newline char. What you're looking for is the terminating null '\0'

Code:

while (preorder[i] != '\0'){
    length++;
    i++;
  }

This can also be simplified to:

Code:

while (!preorder[i])++i;

Of course you could always use strlen()

-Futura