C++ Programming Code Examples
C++ > If Else and Switch Case Code Examples
C++ Program to Check Whether Number is Even or Odd
/* C++ Program to Check Whether Number is Even or Odd
In this example, if...else statement is used to check whether a number entered by the user is even or odd.
Integers which are perfectly divisible by 2 are called even numbers.
And those integers which are not perfectly divisible by 2 are not known as odd number.
To check whether an integer is even or odd, the remainder is calculated when it is divided by 2 using modulus operator %. If remainder is zero, that integer is even if not that integer is odd.
In this program, if..else statement is used to check whether n%2 == 0 is true or not. If this expression is true, n is even if not n is odd. */
#include <iostream>
using namespace std;
int main()
{
int n;
cout << "Enter an integer: ";
cin >> n;
if ( n % 2 == 0)
cout << n << " is even.";
else
cout << n << " is odd.";
return 0;
}
A program shall contain a global function named main, which is the designated start of the program in hosted environment. main() function is the entry point of any C++ program. It is the point at which execution of program is started. When a C++ program is executed, the execution control goes directly to the main() function. Every C++ program have a main() function.
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A return statement ends the processing of the current function and returns control to the caller of the function. A value-returning function should include a return statement, containing an expression. If an expression is not given on a return statement in a function declared with a non-void return type, the compiler issues an error message. If the data type of the expression is different from the function return type, conversion of the return value takes place as if the value of the expression were assigned to an object with the same function return type.
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In computer programming, we use the if statement to run a block code only when a certain condition is met. An if statement can be followed by an optional else statement, which executes when the boolean expression is false. There are three forms of if...else statements in C++: • if statement, • if...else statement, • if...else if...else statement, The if statement evaluates the condition inside the parentheses ( ). If the condition evaluates to true, the code inside the body of if is executed. If the condition evaluates to false, the code inside the body of if is skipped.