1. Control Flow Statements: Repetition/Looping
Pemrograman Dasar
Control Flow Statements:
Repetition/Looping
PTIIK - UB

2. Statements
Control flow statements regulate the order in which statements get executed.
Kinds of control flow statements:
Decision making:
if-then statement
if-then-else statement,
switch-case statement
Repetition/looping:
while statement
for statement
do-while statement
Branching statement:
break statement
continue statement
return statement

3. Repetition/Looping Three forms of repetition statements:
while statements
for statements
do-while statements

4. while statements Syntax: while (boolean_exp) statement; or.. }
statements
true
boolean_exp
false

5. while statements Example: while(product <= 1000)
product = 2*product;
product=2*product;
product <= 1000
true
false

6. break dan continue break continue
Exit from decision-making (switch) or repetition (for, while dan do-while)
continue
Skips the current iteration of a for, while and do-while.

7. break Example: int x = 1; while(x<=10){ System.out.println(x); x++;
if (x>5)
break; }
Exit from the loop

8. continue Example: int x; for(x=1; x<=10; x++) { if (x == 5)
System.out.println(x); }

9. Exercise

10. Exercise Input: Asumsi Maka output-nya:
Berapakah kue untuk si Rakus? …
Asumsi
Misalkan jawaban pertanyaan di atas adalah 5
Maka output-nya:
Si Rakus melihat 5 kue, memakan 1, menyisakan 4
Si Rakus melihat 4 kue, memakan 1, menyisakan 3
Si Rakus melihat 3 kue, memakan 1, menyisakan 2
Si Rakus melihat 2 kue, memakan 1, menyisakan 1
Si Rakus melihat 1 kue, memakan 1, menyisakan piringnya

11. Submission
Deadline: 21 October 2012 To: Subject: [PROGDAS SI…] Si Rakus Content: Nama: NIM: Kelas: Table Source code

12. for statements
You use the basic for statement to loop over a range of values from beginning to end.
for (initialization-expression; loop-expression; update-expression)
statement;
//or
for (initialization-expression; loop-expression; update-expression) { … }

13. for statements
for (exp1; exp2; exp3) statement; exp1: initialization-expression exp2: loop-expression exp3: update-expression The initialization-expression allows you to declare and/or initialize loop variables, and is executed only once. Then the loop-expression of boolean or Boolean type is evaluated and if it is true the statement in the body of the loop is executed. After executing the loop body, the update-expression is evaluated, usually to update the values of the loop variables, and then the loop-expression is reevaluated. This cycle repeats until the loop-expression is found to be false. The presence of exp1, exp2, and exp3 are optional.

14. for statements true false exp1 exp3 statements exp2 exp1 exp3

15. System.out.println(“x =” + x);
for statements
Example:
for (x=1; x <= 10; x++)
System.out.println(“x =” + x);
x = 1
x++
System.out.println(“x =” + x);
true
x<=100
false

16. for statements Examples: int x; for(x=1; x<=10; x++)
System.out.println(x);
int x;
for(x=10; x>=1; x--)
System.out.println(x);

17. for statements Examples:
exp1 and exp3 may consist of more than one expressions, separated by comma(s)
Examples:
int i,j;
for(i=1, j=30; i<j; i++, j--){
System.out.println(i + " -- " + j); }

18. for statements Infinite Loop for(;;){ … } Contoh: int i = 0; for(;;){
printf("%d ", i);
if (i>=10)
break; // break out of the loop }

19. while and for Equivalence of for and while:
exp1; while(exp2){ statement1;
statement2; ….
exp3 }
for(exp1; exp2; exp3){ statement1;
statement2;
…. }
equivalent

20. while and for Equivalence of for and while: Contoh:
exp1; while(exp2){ statement1;
statement2; ….
exp3 }
for(exp1; exp2; exp3){ statement1;
statement2;
…. }
equivalent
int x=1;
while(x<=10){
System.out.println(x);
x++; }
int x;
for(x=1;x<=10;x++)
System.out.println(x);
equivalent

21. Exercise Input: Asumsi Maka output-nya:
Berapakah kue untuk si Rakus? …
Asumsi
Misalkan jawaban pertanyaan di atas adalah 5
Maka output-nya:
Si Rakus melihat 5 kue, memakan 1, menyisakan 4
Si Rakus melihat 4 kue, memakan 1, menyisakan 3
Si Rakus melihat 3 kue, memakan 1, menyisakan 2
Si Rakus melihat 2 kue, memakan 1, menyisakan 1
Si Rakus melihat 1 kue, memakan 1, menyisakan piringnya