Practice Session 2 - Control Flow Statements in C & Applications

This session focuses on understanding and applying control flow statements in the C programming language. Students will practice using conditional statements (if, if-else, nested if, switch-case) and looping constructs (for, while, do-while) to control the execution of programs. The session emphasizes writing efficient C programs that make decisions, perform iterations, and implement logic for real-world applications such as number checks, menu-driven programs, and pattern generation.

1. Nguyễn Trung Hiếu
Practice Session II
IT1016 – 738793

2. Control Flow Statements

3. CFS: Introduction
Fundamental constructs in C.
Enable the execution of different code blocks based on
certain conditions.
Good understanding → Efficient, structured code.

4. CFS: Types
Conditional Statements
Looping Statements
Jumping Statements

5. Conditional Statements

6. CS: Types
if-else
switch
(condition) ? do_if_true : do_if_false

7. CS: if
if (cond) {
do_if_true();
}
other_code();

8. CS: if-else
if (cond) {
do_if_true();
} else {
do_if_false();
}
other_code();

9. CS: nested if-else
if (cond1) {
do_if_true();
if (cond2) { do_if_true_T(); }
else { do_if_true_F(); }
}
else { … }

10. CS: if-else if-else
if (cond1) { do_if_1_true(); }
else if (cond2) { do_if_2_true(); }
…
else (cond3) { … }

11. CS: switch
switch (expression) {
case value1: statements;
case value2: statements;
…
default: statements;
}

12. CS: Ternary Operator
(condition) ? [true_statements] :
[false_statements] ;

13. Looping Statements

14. LS: for
for (init; test; update)
{
…
}

15. LS: nested for
for (init; test; update)
{
for (init2; test2; update2)
{ … }
}

16. LS: while
while (condition)
{
do_something();
}

17. LS: while (1)
while (1)
{
do_something();
break;
}

18. LS: do
do {
something();
} while (condition);

19. LS: do & while
do { something(); }
while (condition);
while (condition)
{ do_something(); }

20. Jump Statements

21. CS: Types
break
continue
return
goto

22. JS: break in loops
for (int i = 0; i < 10; i++) {
do_something();
if (i == 5) { break; }
}
while (cond1) { if (cond2) {break; } }

23. JS: break in loops
for (int i = 0; i < 10; i++) {
for (int j = 0; i < 10; i++) {
if (j == 5) { break; }
}
}

24. JS: break in switch
switch (cond) {
case a: do_st_a(); break;
case b: do_st_b(); break; …
default: do_st_df();
}
do_after_switch();

25. JS: break in switch
What if no break at the end of a case?
switch (cond) {
case a: do_st_a();
case b: do_st_b();
case c: do_st_c(); …
default: do_st_df(); }

26. JS: When not to break?
switch (day) {
case 1: case 2: case 3: case 4:
case 5: printf("Weekday"); break;
case 6: case 7:
printf(“Weekend"); break;
default: printf(“Invalid day"); }

27. JS: continue
Skip the remaining code after the continue statement
within a loop and jump to the next iteration of the loop.

28. JS: continue
for (i = 0; i < 5; i++) {
    if (i == 2) { continue; }
   printf("%d", i);
}