I am getting a bunch of extra chars when i try to reverse a cstring in c++

Question

The string entered by the user appears to be reversed but it is also followed by a bunch of garbage chars. Here is my reverse function:

void reverse(char str[])
{
    char reversed[MAX_CHAR];

    for(int i = 0; i < strlen(str); i++)
    {
        reversed[i] = str[strlen(str) - i - 1];
    }

    cout << reversed << endl;
}

Answer 1

You need to end your string with the NULL character '\0', ASCII value 0.

Try this:

void reverse(char str[]) {
  char reversed[MAX_CHAR];
  int len = strlen(str);

  for(int i = 0; i < len; i++) {
    reversed[i] = str[len - i - 1];
  }

  reversed[len] = '\0'; // Add this

  cout << reversed << endl;
}

This is how C and C++ know where the end of the string is.

Read more about Null-terminated character sequences:

• http://www.cplusplus.com/doc/tutorial/ntcs/
• http://en.wikipedia.org/wiki/Null-terminated_string