Computer Science 101

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Computer Science 101

• The If Statement

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Javas Relational Operators
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Primitive Conditions

• Conditions are expressions which evaluate to true
  or false.
• One kind of condition is the comparison of two
  numerical values of the same type.
• Examples
• Payrate gt 10
• (x10) (yz -8)

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The basic If-Statement

• The syntax for the If-Statement is
  if (condition) statement
• The semantics are as expected -
• the condition is evaluated
• if the condition is true, the statement is
  executed
• The statement may be compound - more than one
  statement enclosed in a pair of

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If-Statement Semantics
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If-Statement examples

• if (yearsWorked gt 10) bonus 1000
• if (age gt 65) total 0.9 total
  numSeniors numSeniors 1

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The If-else-Statement

• The syntax for the If-Else-Statement is
  if (condition) statement-1
  else statement-2
• The semantics are as expected -
• the condition is evaluated
• if the condition is true, then statement-1 is
  executed otherwise, statement-2 is executed
• Either statement may be compound - more than one
  statement enclosed in a pair of

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If-Else-Statement examples

• if (yearsWorked gt 10) bonus 1000
  else bonus 500
• if (age gt 0) total 0.9 total
  numSeniors numSeniors 1 else
  nonSeniors nonSeniors 1

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While I'm resting, you boys ...