# C++ If else

Go to main Page

### if else in C++

In this tutorial, we are going to learn if else in C++ with the help of examples

In computer programming, we use if for running a block of code if the condition is true.

• If marks greater than 85 then the grade is A+
• If marks greater than 75 then the grade is B+
• If marks greater than 70 then the grade is B
• If marks greater than 65 then the grade is B-
• If marks greater than 60 then the grade is C+
• If marks greater than 55 then the grade is C
• If marks greater than 50 then the grade is D
• If marks less than 50 then the grade is F

### Forms of if..else statement

There are three forms of if..else statement.

1. if statement
2. if else statement
3. if else..if else statements

### C++ if Statement

##### Syntax

``````if (condition) {
// body of if statement
}
}
``````

##### Explaination
• if statement evaluates the condition in parentheses
• if a condition is true then the block of code in the body will run.
• if a condition is false then the block of code will skip.
##### Diagram ##### Example :Print positive number entered by user

``````#include <iostream>
using namespace std;

int main() {
int number;

cout << "Enter an integer: ";
cin >> number;

// checks if the number is positive
if (number > 0) {
cout << "You entered a positive integer: " << number << endl;
}
cout << "This statement is always executed.";
return 0;
}
``````

##### Output

``````Enter an integer: 5
You entered a positive number: 5
This statement is always executed.
``````

### C++ if...else

##### syntax

``````if (condition) {
// block of code if condition is true
}
else {
// block of code if condition is false
}
``````

##### Diagram ##### Example :Find whether the number is even or odd.

``````#include <iostream>
using namespace std;

int main()
{
int n;

cout << "Enter a number: ";
cin >> n;

if ( n % 2 == 0)
cout << n << " is even.";
else
cout << n << " is odd.";

return 0;
}``````

##### Output

``````Enter a number: 13
13 is odd.
``````

### C++ if...else if..else

##### syntax

``````if (condition1) {
// code block 1
}
else if (condition2){
// code block 2
}
else {
// code block 3
}
``````

##### Diagram ##### Example :Find whether the number is even or odd.

``````#include <iostream>
using namespace std;

int main() {
int number;

cout << "Enter an integer: ";
cin >> number;
if (number > 0) {
cout << "You entered a positive integer: " << number << endl;
}
else if (number < 0) {
cout << "You entered a negative integer: " << number << endl;
}
else {
cout << "You entered 0." << endl;
}
cout << "This line is always printed.";
return 0;
}``````

##### Output

``````Enter an integer: 1
You entered a positive integer: 1.
This line is always printed.
``````