5.4 "C" Language Constructs -- 1

5.4 "C" Language Constructs -- 1

• Statements
  • Include the termination semicolon
  • Compound statements { & }
  •   while( expression ) statement
    "[T]he expression is evaluated. If it is non-zero, statement is executed, and expression is re-evaluated. This cycle continues until expression becomes zero, at which point execution resumes after statement."
  •   if( expression ) statement
  • if( expression ) statement else statement
  • expression statements
  • main function
• Operators -- 1  

  *	Multiply
  /	Divide
  +	Addition (and unary)
  -	Subtraction (and unary, Negation)
  %	Remainder/mod
  	"If the quotient a/b is representable,
  	the expression (a/b)*b + a%b shall equal a."
  	ANSI "C" Standard 9899 p82.
  =	Assignment
  ++	Pre/post increment
  -	Pre/post decrement

• Comparison Operators -- 1  

  ==	Equality
  >	Greater than
  >=	Greater than or equal
  <	Less than
  <=	Less than or equal

  Note: NEVER is the == comparison operator for floating point values. It may fail even when the numbers "should" be identical. The precision used for registers and computation may exceed the precision used for storage in memory. What this means is that a comparison might fail or pass simply due to register utilization by the compiler.

• Data types -- 1
  • Variables must be declared.
  •   int Integer 16 or 32 bits
  •   float Floating point 32 bits
  •   double Floating point 64 bits
  • Global and auto (scope)

5.4 "C" Language Constructs -- 1