Learn C Function by Example 1 : Underscore and Alphanumerics are allowed

Basic Note :

1. In C Programming Function name should be valid identifier.
2. Valid Identifier includes following -

- Underscore
- Alphabets
- Digits

3. C Function Name always starts with either alphabet or underscore.
4. C Function Name may contain digit as ‘nth’ character where n is not starting character.

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Learn by Program : Valid Example

#include<stdio.h>
void printMessage();
int main()
{
   printMessage();
}
void printMessage(){
   printf("Hello World");
}

Learn by Program : Invalid Example

#include<stdio.h>
void printMessage();
int main()
{
   printMessage();
}
void print Message(){
   printf("Hello World");
}

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[tabs tab1="Valid Function Names" tab2="Invalid Function Names" ] [tab id=1] [checklist]

• addNumber()
• _add()
• print30()

[/checklist] [/tab] [tab id=2] [checklist]

• add Number()
• 30add()
• $print30()

[/checklist] [/tab] [/tabs]