Advanced Loops

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Advanced Loops Switch
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Nested Loops

• Outer Loop
• One or More Inner Loops
• Each time the outer loop is repeated, the inner
  loop in executed (in its entirety)

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Example

• Clock
• Outer Loop ? Hours (12 hours)
• Inner Loop ? Minutes (60 minutes/hour)
• Inner Loop ? Seconds (60 seconds/min)
• For every hour, the minute loop has to run all 60
  times
• For every minute, the seconds loop has to run all
  60 times

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• public class Clock public static void main
  (String args) // begin outer hours loop
• for (int hours 1 hours lt 12 hours )
  // begin inner minutes loop
• for (int minutes 0 minutes lt 59
  minutes) // begin inner seconds loop
• for (int seconds 0 seconds lt 59
  seconds)
  System.out.println (hours "" minutes ""
  seconds) // end seconds
  // end minutes // end hours // end
  main // end clock
• Clock code

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Multiplication Tables

• Write a program that will print a multiplication
  table (1 9) as shown

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Analysis

• Input None
• Process???
• Output Multiplication Table

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Process

• Display the title Row
• Print the table body
• Display the Products

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Process

• Display the Column Headings
• Display the numbers 1 9
• Display Row number
• Display Results (Multiplication)
• Column Heading Row Heading

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Display Column Headings
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Produce Table Body
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Format for Output
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Multiplication Table Code

• MultiplicationTable.java

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Break / Continue

• Keywords to allow additional control to the loop
• break
• Immediately ends the innermost loop
• Often used with an if statement
• continue
• Ends the current iteration of the loop
• ALWAYS inside a loop
• Program control goes to the end of the loop body
• Generally used with an if statement

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Break

• Write a program that adds the integers from 1
  20 until the sum is greater than or equal to 100.
• Input Numbers 1-20
• Process Add the next number (1-20) to the
  previous sum until the sum is greater than or
  equal to 100
• Output The sum of the numbers

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Break
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Continue

• Write a program that will add the integers from
  1-20, except the multiples of 5.
• Input Numbers 1-20
• Process If number is not a multiple of 5, add
  to sum
• Output Sum of numbers 1-20 that are not
  multiples of 5

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Continue
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Switch Statements

• Construct to simplify nested decision statements
• Multiple if statements can make the program
  difficult to read

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Example Nested If

• Ticket Prices
• if (seatingLevel 1)
• ticketPrice 40.00
• else if (seatingLevel 2)
• ticketPrice 30.00
• else if (seatingLevel 3)
• ticketPrice 15.00
• else
• ticketPrice 10.00

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Example - Switch

• switch (seatingLevel)
• case 1
• System.out.println (Orchestra)
• ticketPrice 40.00
• break
• case 2
• System.out.println (Mezzanine)
• ticketPrice 30.00
• break
• case 3
• System.out.println (Balcony)
• ticketPrice 15.00
• break
• default
• System.out.printly (Standing)
• ticketPrice 10.00
• break
• // end case