What is C if tag?
The < c:if > tag is used for testing the condition and it display the body content, if the expression evaluated is true. It is a simple conditional tag which is used for evaluating the body content, if the supplied condition is true.
What is simple if in C?
Working of 'simple if' statement The statement inside the if block are executed only when condition is true, otherwise not. If we want to execute only one statement when condition is true, then braces ({}) can be removed. In general, we should not omit the braces even if, there is a single statement to execute.
What Is syntax of if?
The syntax of the if..else statement is: if (test expression) { // run code if test expression is true } else { // run code if test expression is false }
What is if condition example?
if (score >= 90) grade = 'A'; The following example displays Number is positive if the value of number is greater than or equal to 0 . If the value of number is less than 0 , it displays Number is negative . if (number >= 0) printf("Number is positive\n"); else printf("Number is negative\n");
Why do we use if statement?
An if statement lets your program know whether or not it should execute a block of code. Comparison-based branching is a core component of programming. The concept of an if-else or switch block exists in almost every programming language.
What is if and else in C?
Use if to specify a block of code to be executed, if a specified condition is true. Use else to specify a block of code to be executed, if the same condition is false. Use else if to specify a new condition to test, if the first condition is false. Use switch to specify many alternative blocks of code to be executed.
How do you end an if statement in C?
The break statement ends the loop immediately when it is encountered. Its syntax is: break; The break statement is almost always used with if...else statement inside the loop.
What is nested if in C?
A nested if in C is an if statement that is the target of another if statement. Nested if statements mean an if statement inside another if statement. Yes, both C and C++ allow us to nested if statements within if statements, i.e, we can place an if statement inside another if statement.
What is variables in C?
Variables are containers for storing data values. In C, there are different types of variables (defined with different keywords), for example: int - stores integers (whole numbers), without decimals, such as 123 or -123. float - stores floating point numbers, with decimals, such as 19.99 or -19.99.
How does if condition work?
The IF statement works by checking the expression to see whether a condition is met and returns a value based on the output obtained. For example, based on the criteria, it returns one predetermined value if the condition is found to be true and a different predefined value if the statement is found to be false.
What are unconditional statements in C?
It is a keyword which is used to terminate the loop (or) exit from the block. The control jumps to next statement after the loop (or) block. break is used with for, while, do-while and switch statement. When break is used in nested loops then, only the innermost loop is terminated.
What is else if statement?
if statement - executes some code if one condition is true. if...else statement - executes some code if a condition is true and another code if that condition is false. if...elseif...else statement - executes different codes for more than two conditions. switch statement - selects one of many blocks of code to be ...
What is nested IF statement in C?
Nested If in C Programming is placing If Statement inside another IF Statement. Nested If in C is helpful if you want to check the condition inside a condtion. If Else Statement prints different statements based on the expression result (TRUE, FALSE). Sometimes we have to check even further when the condition is TRUE.
What does if 1 mean in C?
In C Programming only if(0) returns false. Other than this condition”if(0)”, the if statement returns true only. So if(-1) will return true only.
What is nested IF with example?
Every person is eligible for working once he or she is above 18 years otherwise not eligible. Moreover, any organization will offer a job if he or she is above 18 years otherwise no job is guaranteed it means the condition then and there becomes false.
What is a nested IF statement?
Nested IF functions, meaning one IF function inside of another, allow you to test multiple criteria and increases the number of possible outcomes.
What is the if statement?
The if statement allows you to control if a program enters a section of code or not based on whether a given condition is true or false. One of the important functions of the if statement is that it allows the program to select an action based upon the user's input. For example, by using an if statement to check a user-entered password, your program can decide whether a user is allowed access to the program.
What does "else" mean in if?
The "else" statement effectively says that whatever code after it (whether a single line or code between brackets) is executed if the if statement is FALSE.
What is the difference between boolean and not?
The boolean operators function in a similar way to the comparison operators: each returns 0 if evaluates to FALSE or 1 if it evaluates to TRUE. NOT: The NOT operator accepts one input. If that input is TRUE, it returns FALSE, and if that input is FALSE, it returns TRUE.
How to have more than one statement execute after an if statement?
To have more than one statement execute after an if statement that evaluates to true, use braces, like we did with the body of the main function. Anything inside braces is called a compound statement, or a block. When using if statements, the code that depends on the if statement is called the "body" of the if statement. For example:
Why do you capitalize Boolean operators?
In the following discussion of Boolean operators, I will capitalize the Boolean operators in order to distinguish them from normal English. The actual C operators of equivalent function will be described further along into the tutorial - the C symbols are not: OR, AND, NOT, although they are of equivalent function.
What happens if the else statement is true?
If the if statement was true the else statement will not be checked. It is possible to use numerous else if statements to ensure that only one block of code is executed. Let's look at a simple program for you to try out on your own. 1.
When to use "other" in a conditional statement?
Another use of else is when there are multiple conditional statements that may all evaluate to true, yet you want only one if statement's body to execute. You can use an "else if" statement following an if statement and its body; that way, if the first statement is true, the "else if" will be ignored, but if the if statement is false, ...
What does comparison operator in C mean?
Comparison operators in C yield a true or false result meaning they return a numeric 1 or 0.
What does condition 1 mean in a child process?
It means negation. In your case condition 1 will be executed in a parent process, condition 2 in a child process.
What is a fork function?
fork () function will create a subprocess A.K.A. child process. So when the function returns, at that instance there will be 2 processes, which are executing at the same location code-wise. Thus it will return in two copies of the process - we call them as parent & child.
Is there a boolean logic in C?
In plain old C there is not boolean data type but there is boolean logic.
Is a numerical value of 0 a logical false?
In C, a numerical value of 0 is considered a logical false, any other numerical value a logical true. The !-operator negates a logical condition, so when pid is 0 it's true and when pid is not 0, it's false. You could read it as "when there is no pid".
What is the syntax of an if statement in C++?
The syntax of an if statement in C++ is −
What is an if statement?
An if statement consists of a boolean expression followed by one or more statements.
What is #if in C?
#if is a preprocessor directive in C to define conditional compilation. It can be used just like an if condition statement which impacts the compilation process and the executable that is created.
What is ifndef?
Variants of if directive. Two common variants of if directive are: ifndef means if not defined and is same as: Alternative using ifndef is: Alternative using ifdef is: As an advice, when you can use ifdef or ifndef instead of if, use it as it has direct compiler support and allows better performance.
Does i==1 give output?
It will give no output as the expression i==1 evaluates to false even though i is 1. If we add an else part, the idea will be clear. Consider this example:
Can you place variables at compile time?
For example, we cannot place variables at compile time as the values within variables are not resolved at compile time.
What is the if statement in C++?
Use the if statement to specify a block of C++ code to be executed if a condition is true.
How to use conditional statements in C++?
C++ has the following conditional statements: 1 Use if to specify a block of code to be executed, if a specified condition is true 2 Use else to specify a block of code to be executed, if the same condition is false 3 Use else if to specify a new condition to test, if the first condition is false 4 Use switch to specify many alternative blocks of code to be executed
What does "if" mean in a statement?
The if statement evaluates the condition inside the parentheses ( ).
When to use if statement in programming?
In computer programming, we use the if statement to run a block code only when a certain condition is met.
What happens if the condition evaluates true?
If the condition evaluates true, the code inside the body of if is executed. the code inside the body of else is skipped from execution. If the condition evaluates false, the code inside the body of else is executed. the code inside the body of if is skipped from execution.
What happens if the code inside the outer else condition is false?
If false, the code inside the outer else condition is executed, which prints "The number is 0 and neither even nor odd."
How many if.else statements are there in C++?
There are three forms of if...else statements in C++.
Where do we store an integer?
We take an integer as an input from the user and store it in the variable num.
When to use switch statement?
If we need to make a choice between more than one alternatives based on a given test condition, the switch statement can be used. To learn more, visit C++ switch.
Simple Example of #if
Simple Example of #if with Else Part
- In this simple C code, we demonstrate the use of if directive with an else part. We have defined a MACRO named OPENGENUS and check that if it is defined, we will print Yes and if it is not defined, we will print No. Output: If we do not define the MACRO OPENGENUS, it will print No. Consider the following C code: Output:
Simple Example of #if with Multiple Else Part
- In the C code example, we demonstrate if directive with multiple if else parts. We define a MACRO OPENGENUS and check if it is even or odd and print the value accordingly. Output:
Conditions with If Directive
- Note that only conditions that can be evaluated in compile time must be used. For example, we cannot place variables at compile time as the values within variables are not resolved at compile time. The main objective of the conditions is to check the defined MACROs and certain conditions on them. All conditions involving variables or other expressi...
Variants of If Directive
- Two common variants of if directive are: 1. ifndef 2. ifdef ifndef means if not defined and is same as: Alternative using ifndef is: ifdef means if defined and is same as: Alternative using ifdef is: As an advice, when you can use ifdef or ifndef instead of if, use it as it has direct compiler support and allows better performance. Hence, in terms of performance:
Why We Need If Directive?
- We need if directive as this allows us to do compile time conditioning which enables programmers to generate custom code during the compilation process based on various factors like: 1. availablility of library files 2. platform 3. user defined requirements during compile time and much more. In short, this enables a single code base to be globally acceptable. With this, you ha…