C If ... Else

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If

you can use these C Comparison Operators and C Logical Operators to perform different actions for different decisions.

If Syntax

The syntax of the if statement in C programming is:

if (test expression) 
{
   // code
}

How if statement works?

The if statement evaluates the test expression inside the parenthesis ().

• If the test expression is evaluated to true, statements inside the body of if are executed.
• If the test expression is evaluated to false, statements inside the body of if are not executed.

If … Else

Use the else statement to specify a block of code to be executed if the condition is false.

If … Else Syntax

if (test expression) {
    // run code if test expression is true
}
else {
    // run code if test expression is false
}

How if…else statement works?

If the test expression is evaluated to true:

• statements inside the body of if are executed
• statements inside the body of else are skipped from execution

If the test expression is evaluated to false:

• statements inside the body of if are skipped from execution
• statements inside the body of else are executed

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If…else Ladder (else if)

Use the else if statement to specify a new condition if the first condition is false.

else if Syntax

f (test expression1) {
   // statement(s)
}
else if(test expression2) {
   // statement(s)
}
else if (test expression3) {
   // statement(s)
}
.
.
else {
   // statement(s)
}

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Short Hand If…Else (Ternary Operator)

• There is also a short-hand if else, which is known as the ternary operator because it consists of three operands.
• It can be used to replace multiple lines of code with a single line. It is often used to replace simple if else statements

Syntax

variable_= (condition) ? expressionTrue : expressionFalse;

Example

int time = 20;  
(time < 18) ? printf("Good day.") : printf("Good evening.");

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Kiketta

Warning

If the body of an if...else statement has only one statement, you do not need to use brackets {}.

For example, this code:

if (a > b) {
    printf("Hello");
}
printf("Hi");

is equivalent to:

if (a > b)
    printf("Hello");
printf("Hi");

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