SYNTAX for nested if:
IF (logical-expression) THEN
statements
IF (logical-expression) THEN
statements
ELSE
statements
END IF
statements
ELSE
statements
IF (logical-expression) THEN
statements
END IF
statements
END IF
typical example can be
Suppose we need a program segment to read a number x and display its sign.More precisely, if x is positive,
+ is displayed; if x is negative, - is displayed; otherwise, a 0 is displayed.
With an IF-THEN-ELSE-END IF statement,we have a two-way decision (i.e., true or false)
for this code will look as
IF (x > 0) THEN
WRITE(*,*) '+'
ELSE
IF (x < 0) THEN
WRITE(*,*) '-'
ELSE
WRITE(*,*) '0'
END IF
END IF
IF (logical-expression) THEN
statements
IF (logical-expression) THEN
statements
ELSE
statements
END IF
statements
ELSE
statements
IF (logical-expression) THEN
statements
END IF
statements
END IF
typical example can be
Suppose we need a program segment to read a number x and display its sign.More precisely, if x is positive,
+ is displayed; if x is negative, - is displayed; otherwise, a 0 is displayed.
With an IF-THEN-ELSE-END IF statement,we have a two-way decision (i.e., true or false)
for this code will look as
IF (x > 0) THEN
WRITE(*,*) '+'
ELSE
IF (x < 0) THEN
WRITE(*,*) '-'
ELSE
WRITE(*,*) '0'
END IF
END IF