IF Statements
IF
statements are a fundamental control flow structure in ApLang. They allow your program to make decisions and execute specific blocks of code based on certain conditions. Using IF
, ELSE IF
, and ELSE
, you can create flexible programs that respond dynamically to different inputs and scenarios.
IF
The IF
statement checks a condition and executes a block of code if the condition evaluates to TRUE
. It’s the most basic form of decision-making in your program.
Syntax
IF (condition) {
// Code to execute if the condition is TRUE
}
Example: Basic IF Statement
x <- 10
IF (x > 5) {
DISPLAY("x is greater than 5")
}
// Output: "x is greater than 5"
In this example, the condition (x > 5)
is TRUE
, so the code inside the IF
block is executed, displaying "x is greater than 5."
ELSE
The ELSE
statement is used to execute a block of code if the condition in the preceding IF
statement evaluates to FALSE
. It provides an alternative path of execution.
Syntax
IF (condition) {
// Code to execute if the condition is TRUE
} ELSE {
// Code to execute if the condition is FALSE
}
Example: IF-ELSE Statement
x <- 3
IF (x > 5) {
DISPLAY("x is greater than 5")
} ELSE {
DISPLAY("x is not greater than 5")
}
// Output: "x is not greater than 5"
Here, the condition (x > 5)
is FALSE
, so the code inside the ELSE
block is executed, displaying "x is not greater than 5."
ELSE IF
The ELSE IF
statement allows you to check multiple conditions sequentially. If the initial IF
condition is FALSE
, the program checks the ELSE IF
condition. You can chain multiple ELSE IF
statements together to handle various scenarios.
Syntax
IF (condition1) {
// Code to execute if condition1 is TRUE
} ELSE IF (condition2) {
// Code to execute if condition1 is FALSE and condition2 is TRUE
} ELSE {
// Code to execute if none of the above conditions are TRUE
}
Example: IF-ELSE IF-ELSE Statement
x <- 5
IF (x > 5) {
DISPLAY("x is greater than 5")
} ELSE IF (x == 5) {
DISPLAY("x is equal to 5")
} ELSE {
DISPLAY("x is less than 5")
}
// Output: "x is equal to 5"
In this example, the program first checks if x
is greater than 5
. Since this is FALSE
, it moves to the ELSE IF
condition (x == 5)
, which is TRUE
. The code inside the ELSE IF
block is executed, displaying "x is equal to 5."
Nesting IF Statements
You can nest IF
statements within each other to create more complex decision-making structures. This is useful for checking multiple conditions in a hierarchical manner.
Example: Nested IF Statements
x <- 10
y <- 20
IF (x > 5) {
IF (y > 15) {
DISPLAY("x is greater than 5 and y is greater than 15")
} ELSE {
DISPLAY("x is greater than 5 but y is not greater than 15")
}
} ELSE {
DISPLAY("x is not greater than 5")
}
// Output: "x is greater than 5 and y is greater than 15"
In this example, the first IF
statement checks if x
is greater than 5
. Since it is TRUE
, the program moves inside this IF
block and checks the next IF
statement to see if y
is greater than 15
. Since both conditions are TRUE
, it displays "x is greater than 5 and y is greater than 15."
Conclusion
IF
, ELSE IF
, and ELSE
statements are powerful tools in ApLang, allowing you to control the flow of your program based on conditions. By mastering these constructs, you can write programs that respond dynamically to a wide range of inputs and situations, making your code more flexible and adaptable.