CSC 2210 Topics

Draft!

Students are allowed a single (standard-sized) page of notes, possibly double-sided. You cannot simply create a verbatim copy of my notes; you must select key bits of pages and/or write significant parts yourself. You will be required to turn in the page at the end of the exam.

• See exam 1, exam 2 review
• Memory maps
  • Draw a memory map for double a, *b, **c; b = &a; c = & b; **c = 1.2;
• Declare identifier before can use it
  • When can an identifier be used before declaration?
• const
  • Is the following legal? void p(const int &x); p(3);
  • Write a function double that takes a value (of any type) and returns that value added to itself without changing the value. Write a fragment of code applying double to some declared, initialize variable, where the type of the variable is in namespace std.
• Arrays in C++ vs. Java, allocating array on stack vs. heap
  • Declare and define a variable names that is an array of pointers to std::string values. Allow up to 20 names. Set the first name to your own name, but all of the rest should be nullptr.
  • C & C++ arrays are passed by reference. Use a struct to create an array that is passed by value.
  • Are Java arrays passed by reference or value?
  • Assume you are implementing void dosomething(int nums[]); and write int s = sizeof(nums); in the body. What does this set s to? Is there a way to change the declaration of nums so s gets a different value?
  • Why are arrays not very useful in Java? Why are they more useful in C++?
  • What methods are available for C++ arrays?
• Declaring, dereferencing pointers
  • Given char *p, knowing the difference between p, *p, and &p
• Count number of negative values in an array of doubles without using []
• nullptr
• Initial value of int xs[100]; (depending on where declared)
• Floating-point constants: 6.022e23

Note 11: C

• goals
• differences, similarities to C++
• compilation units, linker, static, extern
  • Explain what the linker does. Give as much detail as you can, being sure to go beyond "combines object files".
• Makefiles; capturing dependencies and actions, make command
  • Write a makefile entry for a command doit if doit reads files p and q and generates r
• printf/scanf to print/read an integer, string, character
• arrays vs. pointers, computing addresses
• typedef struct { ... } name;
• passing structs as parameters
• C-style strings, strlen, strcpy, strcat, strcmp
• two-dimensional arrays, computing addresses with 2-d arrays
• #define, dangers of using #define instead of templates
• #if ... #else ... #endif

Note 12: memory in C (& C++), stacks

• be able to explain how stack is managed: what is FP, why FP-1 might be first local variable, given a layout how is data stored in that layout (including with pointers)
• memory layout: text, rodata, data, bss, heap, stack
• using malloc and free

Note 13: Overloading/copy/move, STL, strings

• Rule of 5: what are the items, why they are needed
• recognize move constructor, explain what it does
• write copy constructor
• explain elements of assignment operator
• describe which operator is used in auto x = a; vs. x = b;.
• given std::string x;, risk of storing x.c_str() in a variable/object

Note 14: Streams, formatting

• passing istream, ostream by reference
• eof-controlled-loop pattern; why

          while ( ! eof ) { read; process }
  

  is a bad idea
• purpose of stringstream: convert other data types into strings or from strings
• using ifstream to read files, ofstream to write

Note 15: Containers, algorithms

• list<T>::iterator, list<T>::const_iterator, vector<T>::iterator, vector<T>::const_iterator
• begin: first element
• end: just after last element
• Example: if std::vector<double> nums(100); gives an array of 100 items, begin() returns &nums[0] and end() returns &nums[100]
• roll of #include <algorithm>; esp sort, reverse, fill
• arguments to sort, reverse: iterators

Note 16: Types

• three definitions of a type
• How static, dynamic types work: what has to be done at runtime for dynamic types, compile time for static types
• advantages, disadvantages of int8_t, int16_t, etc.
• what void* means, how used in C
• differences between C and C++ type systems
• casting using (type)
• Ada and type equivalence rule based on names
• Dangers of Ada's name equivalence type system
• strongly typed: same results on all machines independent of representations
• what it means to create a function pointer, how it is useful in C

Note 17: How Computers Work

• basic gates: AND, OR, NOT - be able to compute result
  • I will give you an interpretation key
• What a MUX does
• Processor elements
• Levels 1-6 of the computing abstraction list