Expressions

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Chapter 4 Functions Instructor Bindra
Shrestha University of Houston Clear Lake
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Acknowledgement Structured Programming
Approach Using C By Behrouz A. Forouzan and
Richard F. Gilberg  
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Function Modules
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Function calls
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Parameters and Return
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Void Parameter and Void Return
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Pass by Value, Return Void
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Pass by Value
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Function Defination
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Passing two values by copy

• A compound assignment is a shorthand notation for
  a simple assignment.
• Compound assignment operators are
• , /, , , and -
• For exampleFor xy, equivalent simple
  expression is x x y
• Similarly,
• x / y is x x/y
• x - y 4 is x x- ( y 4)
• x y is x x y
• x y2 is x x ( y 2).

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• The postfix increment/decrement operates at the
  second level of the Precedence Table ( see inside
  front cover)
• a Here a is an operand while is a postfix
  operator.
• a has the same effect as a a1.
• Although the result of both expression is the
  same, there is a major difference.For example If
  variable a contains 4 before the expression is
  evaluated, the value of the expression a is 4
  
• After the evaluating the expression and its side
  effects, then only a becomes 5.
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Different ways of calling

• include ltstdio.hgt
• int main (void) / example of Postfix
  increment/
• int a
• a 5
• printf("d\t", a)
• printf("d\t", a)
• printf("d\n", a)
• return 0
• / Results
• 5 5 6
• /

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One-way communication
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Two-way communication
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Two-way swapping values example
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Mixed communication
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Variable Scopes