COMP102

1
COMP102 Programming Fundamentals I

• LA2B (Mon 5-7pm)
• LA2E (Fri 3-5pm)
• LA2F (Fri 5-7pm)
• TA Jackie Lo

2
Lecture Review

• Logically controlled loops
• Pre-test loop
• while loops
• Post-test loop
• do-while loops
• Counter-controlled loops
• for loops

3
Lecture Review

• while Loop
• Use Boolean expression to control the iteration
• Check condition before action
• Syntax
• while (condition fulfilled)
• action
• Operation
• Whenever (condition true)
• Repeat the action

4
Lecture Review

• do-while Loop
• Use Boolean expression to control the iteration
• Check condition after action
• Syntax
• do action
• while (condition fulfilled)
• Operation
• Repeat the action
• Whenever (condition true)

5
Lecture Review

• for Loop
• Use counter to control the iteration
• Update counter and check condition after action
• Syntax
• for ( initial condition update)
• action

6
Lecture Review

• Exam skills (Reading code segment)
• Input 5
• Output?
• Result 120

cin gtgt n f 1 c 1 while (c lt n) f
c c 1 coutltltResult ltltfltltendl
7
Lecture Review

• / --
• Special operators for incrementing / decrementing
  an integer by 1
• E.g.
• j k
• j k
• k k 1
• j --k
• k k 1
• j k

8
Summary

• By the end of this lab, you should be able to
• Implement loops
• for/while/do-while statement
• Distinguish between pre-/post-increment

9
Lab3

• Prefix Postfix shortcut

include ltiostreamgt using namespace std int
main() int i 1 cout ltlt "i " ltlt i ltlt
endl // postfix form cout ltlt "i " ltlt
i ltltendl cout ltlt "i " ltlt i ltlt endl i
1 // prefix form cout ltlt "i " ltlt i
ltltendl cout ltlt "i " ltlt i ltlt endl return 0
10
Lab3

• Use Loop

//repeat //initialization //repeat //rep
eat //Ask user to input a guess //
whenever guess not valid //Now guess is valid
// According to the guess, // output Too
high or Too low //increase no of
attempts // whenever guess ! random
no //Now guess random no //According to no
of attempts, output comments //repeat //Ask
user to continue //whenever respond not
valid //whenever user wants to continue cout
ltlt"Good bye!"ltltendl