Strings and Pointer Arrays

1
Strings and Pointer Arrays

• Speaker Yao-Ting Huang
• Advisor Kun-Mao Chao

National Taiwan University Department of Computer
Science Information Engineering Algorithms and
Computational Biology Lab.
2
Pointer Arrays (1/2)

• A pointer variable contains the memory address
  where the actual value is stored.
• char a declares a char pointer which points to
  the initial memory address of a string.
• You can represent strings by arrays or pointers.
• e.g., char n is the same as char n
• An array of strings can be represented by an
  array of char pointers.
• e.g., int main(int argc, char argv)
• argv0 ltgt char ltgt a string
• argv1 ltgt char ltgt a string

3
Pointer Arrays (2/2)

• char argv is an array of char.
• char argv is an array of strings.
• When your program is invoked, the input arguments
  are passed to the main function as an array of
  strings.
• e.g., C\Run parameter1 parameter2
• char argv stores all the input arguments.
• Since each array element is a char pointer (i.e.,
  a string), we can print each input argument by
• fprintf(s\n, argv0)
• fprintf(s\n, argv1)

4
Final Project

• You have to join a group composed of 5 to 7
  people.
• Please hand in the list of group members and
  email to both TA.
• TAs will discuss with each individual group at
  12/9 and 12/23.
• Each group should submit your proposal for final
  project by 12/2.
• Each group should present your proposal at that
  day.
• TA will correct your proposal in your
  presentation.
• The students in both class A and class B should
  attend the class in PM 120.

5
Outline of Lecture Today

• Demo of your Homework 5.
• Please make sure your program is ready to
  execute.
• Reform the project groups.