64 lines
1.4 KiB
Markdown
64 lines
1.4 KiB
Markdown
---
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title: If
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---
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# If
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The if statement executes different blocks of code based on conditions.
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```
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if (condition) {
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// Do something when `condition` is true
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}
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else {
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// Do something when original if `condition` is false
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}
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```
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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.
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```
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if (condition) {
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// Do something if `condition` is true
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}
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else if (anotherCondition) {
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// Do something if `anotherCondition` is true
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}
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else {
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// Do something if `condition` AND `anotherCondition` is false
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}
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```
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Note: `else` and `else if` sections are not required, while `if` is mandatory. Furthermore, `else` and `else if` can only be used following an `if` statement. In the instance when one `if` statement is executed, the following `else if` and `else` statements are ignored.
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## Example
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```
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#include <stdio.h>
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int main () {
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// Local variable definition
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int a = 100;
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// Check the boolean condition
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if(a < 5) {
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// If condition is true then print the following
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printf("a is less than 5!\n" );
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}
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else {
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// If condition is false then print the following
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printf("a is not less than 5!\n" );
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}
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printf("Value of a is : %d\n", a);
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return 0;
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}
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```
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## Output
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```
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-> a is not less than 5!
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-> Value of a is : 10
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```
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