freeCodeCamp/guide/english/c/if/index.md

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---
title: If
---
# If
The if statement executes different blocks of code based on conditions.
```
if (condition) {
// Do something when `condition` is true
}
else {
// Do something when original if `condition` is false
}
```
When `condition` is true, code inside the `if` section executes, otherwise `else` executes. Sometimes you would need to add a second condition. For readability, you should use a `else if` rather than nesting `if` statements.
```
if (condition) {
// Do something if `condition` is true
}
else if (anotherCondition) {
// Do something if `anotherCondition` is true
}
else {
// Do something if `condition` AND `anotherCondition` is false
}
```
Note that the `else` and `else if` sections are not required, while `if` is mandatory.
## Example
```
#include <stdio.h>
int main () {
// Local variable definition
int a = 100;
// Check the boolean condition
if(a < 5) {
// If condition is true then print the following
printf("a is less than 5!\n" );
}
else {
// If condition is false then print the following
printf("a is not less than 5!\n" );
}
printf("Value of a is : %d\n", a);
return 0;
}
```
## Output
```
-> a is not less than 5!
-> Value of a is : 10
```