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. An if can have zero or one else's and it must come after any else if's. The syntax of an if...else statement in C programming language is −. If the condition is true, the statements inside if statement are executed, otherwise they are skipped. These generally have two values of LHS and RHS. When using if...else if..else statements, there are few points to keep in mind −. An if statement identifies which statement to run based on the value of a Boolean expression. (A && B) is false. These conditions are specified by a set of conditional statements having boolean expressions which are evaluated to a boolean value true or false. The above two ‘if’ statements behave the same in C-like languages. The syntax of an 'if' statement in C programming language is − if (boolean_expression) { /* statement (s) will execute if the boolean expression is true */ } If the Boolean expression evaluates to true, then the block of code inside the 'if' statement will be executed. The problem here is a common one, a mistake made by just about every C programmer from time to time: The trailing semicolon (Line 10) tells the program that the if statement has nothing to do when the condition is true. So an IF statement can have two results. An if statement can be followed by an optional else statement, which executes when the Boolean expression is false. The IF-ELSE statement is used to follow a certain set of instructions based on the result of a decision. An if statement consists of a Boolean expression followed by one or more statements. So lets take a look at an example: In the example above the user can input a number. Now take a look at the “if statement”: if the number stored in the variable A is equal to ten, then “is equal” is printed on the screen. C++ supports the usual logical conditions from mathematics: Less than: a < b Less than or equal to: a <= b Greater than: a > b Greater than or equal to: a >= b Equal to a == b; Not Equal to: a != b You can use these conditions to perform different actions for different decisions. If both the operands are non-zero, then the condition becomes true. Following table shows all the logical operators supported by C language. It is one of the powerful conditional statement. The statement that begins with if constexpr is known as the constexpr if statement. True is always a non-zero value, and false is a value that contains zero. Now take a look at the “if statement”: if the number stored in the variable mynumber is equal to ten, then print “is equal” on the screen. In the example above, time (22) is greater than 10, so the first condition is False.The next condition, in the else if statement, is also False, so we move on to the else condition since condition1 and condition2 is both False - and print to the screen "Good evening". The && operator is a short-circuiting operator. That’s because a single semicolon is a complete statement in C, albeit a null statement. C else-if Statements - else-if statements in C is like another if condition, it's used in a program when if statement having multiple decisions. Syntax of C programming conditional operator It takes three operands. Starting in C++17, an if statement may also contain an init-statement expression that declares and initializes a named variable. The else..if statement is useful when you need to check multiple conditions within the program, nesting of if-else blocks can be avoided using else..if statement. C – else..if statement. The Boolean expression must return either a true or false value. An if statement, in C#, is a programming construct in C# used to selectively execute code statements based on the result of evaluating a Boolean expression. However, if the time was 14, our program would print "Good day." Practice exercise - if...else programming exercises in C. For example, =IF (C2=”Yes”,1,2) says IF (C2 = … C programming language assumes any non-zero and non-null values as true and if it is either zero or null, then it is assumed as false value. Use of the conditional operator instead of an if-else statement might result in more concise code in cases when you need conditionally to compute a value. In a constexpr if statement, the value of condition must be a contextually converted constant expression of type bool. The If statement in C programming is one of the most useful decision-making statements in real-time programming. Here function1() is guaranteed to execute first.. The following example demonstrates two ways to classify an integer as negative or nonnegative: Ternary operators can be nested just like if-else statements… If the Boolean expression evaluates to false, then the first set of code after the end of the 'if' statement (after the closing curly brace) will be executed. Once an else if succeeds, none of the remaining else if's or else's will be tested. If statement is always used with a condition. The syntax of an 'if' statement in C programming language is −. The number is stored in the variable mynumber. It is used when a single condition is to be checked. 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. In other words: if a specific statement is true, execute this instruction. The condition enclosed in if statement decides the sequence of execution of instruction. C – else..if statement. In the following example, the bool variable condition is set to true and then checked in the if statement. If else Statement in C programming language, when we need to execute a block of statements that too when a particular condition is met or not met that situation is known as decision making. In computer programming, we use the if statement to run a block code only when a certain condition is met. Before moving to next tutorial, must try some exercises based on if...else statement. C Tutorials C Programs C Practice Tests New . Check the Testing Expression: An if-then-else statement can test expressions based on ranges of values or conditions, whereas a switch statement tests expressions based only on a single integer, enumerated value, or String object. Remember that the arguments value_if_true and value_if_false must be of the same type, and they must be simple expressions rather than full statements. The conditional operator is kind of similar to the if-else statement as it does follow the same algorithm as of if-else statement but the conditional operator takes less space and helps to write the if-else statements in the shortest way possible.. Syntax: The conditional operator is of the form . The following C program generate a random number using rand() function of . Example explained. This section covers the concept of if-else statement in C. It ignores the alignment of expressions on the page. C If statement allows the compiler to test the condition first, and then, depending upon the result, it will execute the statements. This operator compares the expression of the left-hand side and right-hand side. The else..if statement is useful when you need to check multiple conditions within the program, nesting of if-else blocks can be avoided using else..if statement. || Called Logical OR Operator. The condition is evaluated first before executing any statement inside the body of If. The first result is if your comparison is True, the second if your comparison is False. C if statement accepts boolean values – if the value is true then it will execute the block of statements below it otherwise not. The syntax of the if statement in C programming is: if (test expression) { // statements to be executed if the test expression is true } How if statement works? The ability to control the flow of your program, letting it make decisions on what code to execute, is valuable to the programmer. The syntax of an if statement in C++ is − if (boolean_expression) { // statement (s) will execute if the boolean expression is true } If the boolean expression evaluates to true, then the block of code inside … If the condition returns false then the statements inside “if” are skipped. If the condition is true, the statements inside if statement are executed, otherwise they are skipped. 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