C Programming Code Examples
C > If Else and Switch Case Code Examples
Check if a Number is Positive or Negative Using Nested if...else
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
/* Check if a Number is Positive or Negative Using Nested if...else
This program takes a number from the user and checks whether that number is either positive or negative or zero. */
#include <stdio.h>
int main()
{
double number;
printf("Enter a number: ");
scanf("%lf", &number);
// true if number is less than 0
if (number < 0.0)
printf("You entered a negative number.");
// true if number is greater than 0
else if ( number > 0.0)
printf("You entered a positive number.");
// if both test expression is evaluated to false
else
printf("You entered 0.");
return 0;
printf("C Programming Language Code Examples");
}
Read formatted data from stdin. Reads data from stdin and stores them according to the parameter format into the locations pointed by the additional arguments. The additional arguments should point to already allocated objects of the type specified by their corresponding format specifier within the format string. In C programming, scanf() is one of the commonly used function to take input from the user. The scanf() function reads formatted input from the standard input such as keyboards. The scanf() function enables the programmer to accept formatted inputs to the application or production code. Moreover, by using this function, the users can provide dynamic input values to the application.
Relational Operators are the operators used to create a relationship and compare the values of two operands. For example, there are two numbers, 5 and 15, and we can get the greatest number using the greater than operator (>) that returns 15 as the greatest or larger number to the 5. Following are the various types of relational operators in C. Equal To Operator (==) is used to compare both operands and returns 1 if both are equal or the same, and 0 represents the operands that are not equal. Not Equal To Operator (!=) is the opposite of the Equal To Operator and is represented as the (!=) operator. The Not Equal To Operator compares two operands and returns 1 if both operands are not the same; otherwise, it returns 0.
Writes the C string pointed by format to the standard output (stdout). If format includes format specifiers (subsequences beginning with %), the additional arguments following format are formatted and inserted in the resulting string replacing their respective specifiers. printf format string refers to a control parameter used by a class of functions in the input/output libraries of C programming language. The string is written in a simple template language: characters are usually copied literally into the function's output, but format specifiers, which start with a % character, indicate the location and method to translate a piece of data (such as a number) to characters. "printf" is the name of one of the main C output functions, and stands for "print formatted". printf format strings are complementary to scanf format strings, which provide formatted input (parsing). In both cases these provide simple functionality and fixed format compared to more sophisticated and flexible template engines or parsers,
The if...else statement executes two different codes depending upon whether the test expression is true or false. Sometimes, a choice has to be made from more than 2 possibilities. The if...else ladder allows you to check between multiple test expressions and execute different statements. In C/C++ if-else-if ladder helps user decide from among multiple options. The C/C++ if statements are executed from the top down. As soon as one of the conditions controlling the if is true, the statement associated with that if is executed, and the rest of the C else-if ladder is bypassed. If none of the conditions is true, then the final else statement will be executed.
#include is a way of including a standard or user-defined file in the program and is mostly written at the beginning of any C/C++ program. This directive is read by the preprocessor and orders it to insert the content of a user-defined or system header file into the following program. These files are mainly imported from an outside source into the current program. The process of importing such files that might be system-defined or user-defined is known as File Inclusion. This type of preprocessor directive tells the compiler to include a file in the source code program. Here are the two types of file that can be included using #include:
In C, the "main" function is treated the same as every function, it has a return type (and in some cases accepts inputs via parameters). The only difference is that the main function is "called" by the operating system when the user runs the program. Thus the main function is always the first code executed when a program starts. main() function is a user defined, body of the function is defined by the programmer or we can say main() is programmer/user implemented function, whose prototype is predefined in the compiler. Hence we can say that main() in c programming is user defined as well as predefined because it's prototype is predefined. main() is a system (compiler) declared function whose defined by the user, which is invoked automatically by the operating system when program is being executed.
The above approach to list Even Numbers is not optimal. It unnecessarily iterates for odd numbers which is a performance issue and to overcome this start the loop with first even...
This is the C sender program using Message Queues. A message queue program code that shows a client server implementation. Enter some message text you want to send.
