برمجة

• Recursive function


  A function that calls itself
• Recursive function


  1. Determine the size factor

  2. Determine the base case(s)

  3. Determine the general case(s)

  4. Verify the algorithm
• Base case


  The one for which you know the answer
• General case


  The one where the problem is expressed as a smaller version of itself
• Three-Question Verification Method


  1. The Base-Case Question

  2. The Smaller-Caller Question

  3. The General-Case Question
• When a function is called, an activation record is stored into a stack (run-time stack)
• When a recursive function is called, there is really no difference between recursive and nonrecursive calls
• Structure


  A data structure used to process data of multiple data types
• Structure example


  • Student Record
  • Name (a string)
  • HW Grades (an array of 3 doubles)
  • Test Grades (an array of 2 doubles)
  • Final Average (a double)
• Structure member


  Each thing in a structure
• Structure members have a name, a type and a value
• Names of structure members follow the rules for variable names
• Types of structure members can be any defined type
• Using a struct


  By defining a structure you create a new data type
• Accessing members


  You can treat the members of a struct just like variables, using the member access operator '.'
• Structure assignment


  You can use structures just like variables, copying the entire structure
• If a member is a pointer, copying means copying the pointer (not what is pointed to)
• Pointers to structures


  There is another member access operator used with pointers: '->'
• Sample Function


  • void update_average(StudentRecord *stu)
  • Calculate total of hw and test grades
  • Set the average