Recursion is expressing an entity in terms of itself. In C programming, recursion is achieved using functions known as recursive function. Recursive functions are very powerful in solving and expressing complex mathematical problems.
Until now, we called a function from another function. However, C language allows a function to call itself known as Recursive function.
A function is a sub-part of a program that contains a collection of statements grouped together to perform some specific task. Functions in C programming is categorized in two category –
A function is a collection of statements grouped together to do some specific task. It may return a value. However, in no case a function will return more than one value. What does it mean by returning a value and where it is returned? To understand this let us consider an example.
Function arguments are the inputs passed to a function. A function must declare variables to accept passed arguments. A variable that accepts function argument is known as function parameter.
In programming function argument is commonly referred as actual parameter and function parameter is referred as formal parameter. I will be using these words interchangeably throughout this series of C programming tutorial.
A function is a collection of statements grouped together to do some specific task. In series of learning C programming, we already used many functions unknowingly. Functions such as – printf(), scanf(), sqrt(), pow() or the most important the main() function. Every C program has at least one function i.e. the main() function.
Write a C program to swap two numbers using pointers and functions. How to swap two numbers using call by reference method. Logic to swap two number using pointers in C program.
Example
Input
Input num1: 10 Input num2: 20
Output
Values after swapping: Num1 = 20 Num2 = 10
Write a C program to remove extra spaces, blanks from a string. How to remove extra blank spaces, blanks from a given string using functions in C programming. Logic to remove extra white space characters from a string in C.
Example
Input
Input string: Learn C programming at Codeforwin.
Output
String after removing extra blanks: "Learn C programming at Codeforwin"
Write a C program to replace all occurrence of a character with another in a string using function. How to replace all occurrences of a character with another in a string using functions in C programming. Logic to replace all occurrences of a character in given string.
Example
Input
Input string: I_love_learning_at_Codeforwin. Input character to replace: _ Input character to replace with: -
Output
String after replacing '_' with '-': I-love-learning-at-Codeforwin
Write a C program to replace last occurrence of a character with another in a given string. How to replace last occurrence of a character with another character in a given string using functions in C programming. Logic to replace last occurrence of a character with another in given string.
Example
Input
Input string: Do you love programming. Input character to replace: . Input character to replace with: ?
Output
String after replacing last '.' with '?' : Do you love programming?
Write a C program to trim both leading and trailing white space characters in a string using loop. How to remove both leading and trailing white space characters in a string using loop in C programming. Logic to delete all leading and trailing white space characters from a given string in C.
Example
Input
Input string: " Lots of leading and trailing spaces. "
Output
String after removing leading and trailing white spaces: "Lots of leading and trailing spaces."