Programming Languages: Input and Output --> Compound Statements

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Programming Languages Input and Output --gt
Compound Statements
Carey Beth Robillard
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Programming Language

• a language with limited words and limited rules
  designed to solve problems on a computer
• most common languages is the C language,
  developed by Dennis Ritchie.

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More to come...

• Input and Output
• Expressions
• Operator and Operand
• Statements

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Input

• Data are input by either
• a statement
• predefined function.

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Input Continued

• example scanf function reads data from the
  keyboard and stores it in a variable
• scanf (d, num)
• d prepares the program for an integer
• Value is stored in the variable num

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Output

• Data are output by either
• a statement
• predefined function

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Output Continued.

• In C language, the printf function displays a
  string on the monitor
• Printf (The value of the number is d , num )

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Expressions

• a sequence of operands and operators that reduces
  to a single value
• example expression for 10 2 5

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Operator

• a language specific token that requires an action
  to be taken.
• most familiar are drawn from mathematics.
• example asterisk () means multiplication.

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Arithmetic Operators
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Arithmetic Operators Continued
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Other Operators

• Relational operators compare data to see if a
  value is greater than, less than, or equal to
  another value.
• Logical Operators combine logical values (true or
  false) to get a new value.
• Assignment operators store values in a variable.

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Some Relational Operators
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Logical Operators
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Some Assignment Operators
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Operands

• receives an operators action
• for any given operator, there may be multiple
  operands
• in arithmetic example, operands of multiplication
  are the multiplier and the multiplicand.

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Statements

• causes an action to be performed by a program
• translates into executable computer language.
• C language has 6 types of statements expression,
  compound, labeled, selection, iterative, and jump.

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Statements Continued

• Expression is turned into a statement by placing
  a semicolon after it. When C sees the semicolon,
  it performs the evaluation on the expression.
• Examples a b 4 and c b c 4

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Compound Statement

• A compound statement is a unit of code consisting
  of zero or more statements. It is also known as a
  block.
• The compound statement allows a group of
  statements to become one single entity.

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The End