4_Control_Structures

# 4_Control_Structures - C Control Structures CMPE13 Cyrus...

This preview shows pages 1–12. Sign up to view the full content.

CMPE13 Cyrus Bazeghi C Control Structures

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
CMPE13 C ONTROL S TRUCTURES Conditional making a decision about which code to execute, based on evaluated expression if if-else switch Iterative executing code multiple times, ending based on evaluated expression for while do-while 2
CMPE13 IF if(condition) action; condition action T F Condition is a C expression, which evaluates to TRUE (non- zero) or FALSE (zero). Action is a C statement, which may be simple or compound (a block). 3

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
CMPE13 E XAMPLES OF IF STATEMENTS if (x <= 10) y = x * x + 5; if (x <= 10) { y = x * x + 5; z = (2 * y) / 3; } if (x <= 10) y = x * x + 5; z = (2 * y) / 3; compound statement; both executed if x <= 10 only first statement is conditional; second statement is always executed (indentation doesn’t help) 4
CMPE13 A BOUT BRACES INDENTATION if(x <= 10) { y = x * x + 5; z = (2 * y) / 3; } if(x <= 10) { y = x * x + 5; z = (2 * y) / 3; } Good style: the braces are aligned (*) Different “ style: the braces are not aligned (*) (*) Source: My opinion 5

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
CMPE13 M ORE IF EXAMPLES kids += 1; if(month == 4 || month == 6 || month == 9 || month == 11) printf(“The month has 30 days. \ n”); if(x = 2) y = 5; This is a common programming error ( = instead of == ), not caught by compiler because it’s syntactically correct. always true, so action is executed! 6
CMPE13 IF S CAN BE NESTED if (x == 3) if (y != 6) { z = z + 1; w = w + 2; } if ((x == 3) && (y != 6)) { z = z + 1; w = w + 2; } is the same as. .. 7

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
CMPE13 IF - ELSE if(condition) action_if; else action_else; condition action_if action_else T F else allows choice between two mutually exclusive actions without re-testing condition. 8
CMPE13 M ATCHING ELSE WITH IF Else is always associated with the closest unassociated if. if(x != 10) if(y > 3) z = z/2; else z = z * 2; if(x != 10) { if(y > 3) z = z/2; else z = z*2; } is the same as. .. if (x != 10) { if (y > 3) z = z/2; } else z = z*2; and is NOT the same as. .. This code 9

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
CMPE13 C HAINING I F S AND E LSE S if (month == 4 || month == 6 || month == 9 || month == 11) printf (“Month has 30 days. \ n”); else if (month == 1 || month == 3 || month == 5 || month == 7 || month == 8 || month == 10 || month == 12) printf (“Month has 31 days. \ n”); else if (month == 2) printf (“Month has 28 or 29 days. \ n”); else printf (“Don’t know that month. \ n”); 10
WHILE while (test) loop_body; test loop_body T F Executes loop body as long as test evaluates to TRUE (non-zero). Note: Test is evaluated

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

### Page1 / 41

4_Control_Structures - C Control Structures CMPE13 Cyrus...

This preview shows document pages 1 - 12. Sign up to view the full document.

View Full Document
Ask a homework question - tutors are online