COMP102 – Programming Fundamentals I LA2B (Mon 5-7pm) LA2E (Fri 3-5pm) LA2F (Fri 5-7pm) TA: Jackie Lo

1. Introduction to Computer Systems Hardware  Input  Process  Memory  Output Software  System Operating system Translation System  Application

2. Data Types, Variables and Constants Data Types  void, int, char, float, double, bool Variables Name / Identifiers Name  Start with a-z/A-Z  Contain only a-z/A-Z/0-9/$/_  Case sensitive Variables Declaration  ;  = ;

2. Data Types, Variables and Constants Constants  Never changed in the program  const = ; Type casting  int( )  double( )  bool( ) Common Mistakes  char a = A; Should be char a = ‘A’;false for 0, true for others1 for true, 0 for falseascii value of characterstruncate the decimal place

3. Structure of C++ Programs #include  using namespace std;  Match with, for time()for srand()/rand()for cin/coutfor setw()/setprecision()

3. Structure of C++ Programs cin >>  User input cout <<  Screen output Common mistakes  cin >>a<<endl; Should be cin>>a; cout<<endl;

3. Structure of C++ Programs Rules for division  double / double = double  double / int = double  int / double = double  int / int = int Random number  srand(time(0));  int ran = rand() % x; truncate the decimal placeRandom no: 0 to x-1

3. Structure of C++ Programs Order of Precedence  Parentheses ( … )  Post-increment/decrement i++ i--  Unary operators !  Pre-increment/decrement ++i --i  Multiplicative operators * / %  Additive operators + -  Relational ordering = >  Relational equality == !=  Logical and &&  Logical or ||  Assignment = += -= *= /= %=

4. Selections condition action true false if statement condition action true false action if-else statement

4. Selections condition action true false action if-else if statement condition action false true selector action Value1 action switch statement action Value2 Value3

4. Selections Truth Table E1E2E1 && E2 true false truefalse E1E2E1 || E2 true falsetrue falsetrue false E!E truefalse true

5. Loops for loop  for(i= ; i ; i ) {…} while loop  while ( ) {…} do-while loop  do {…}  while ( )

6. Functions Return statement  void = no return statement or return nothing  other = return value to the caller through the function name Pass by value  parameters inside and outside functions is not related Pass by reference  parameters inside and outside functions is related  Value changed inside functions will affect outside  Value changed outside functions will affect inside

6. Functions (03 past paper Q6) #include <iostream.h> int Test(int&, int, int&); int a = 2; int b = 3; int main() { int b = 4; int c = 5; int d ; d = Test(a, b, c); b = b + 3; cout << a << ' ' << b << ' ' << c << ' ' << d << endl; return 0; } int Test(int& z, int x, int& y) { z = 3; x = b; a = y + a; cout << z << ' '<< --x << ' ' << y++ <<' ' << a << endl; return (y - x); }