If-Then-Else Statement
An if-then statement can be followed by an optional else statement, which executes when the Boolean expression is false.
Syntax
if <condition> then <S1> else <S2>
Where condition is a relational expression and S1, S2 are simple or compound statements. In the if-then-else statements, when the test condition is true, the statement S1 is executed and S2 is skipped; when the test condition is false, then S1 is bypassed and statement S2 is executed.
Flow Diagram
// keep
Example
program exIfThenElse (input, output, error);
import * from io;
var a : integer;
begin
a := 100;
if a < 20 then
writeln("a is less than 20")
else
writeln("value of a is " + string(a));
end.
Output:
value of a is 100