GCD and LCM Using Recursion in C – Euclidean Algorithm

This C program finds GCD and LCM using recursion with the Euclidean algorithm. The GCD (Greatest Common Divisor) is the largest number that divides both inputs with no remainder. The LCM (Least Common Multiple) is the smallest number divisible by both. Once the GCD is known, the LCM follows from a simple identity: GCD(a, b) …

Fibonacci Series in C – Iterative, Recursive, and Array Methods

The Fibonacci series in C is a sequence where each number is the sum of the two preceding ones, starting from 0 and 1: 0, 1, 1, 2, 3, 5, 8, 13, 21, 34, … This page covers three approaches — iterative series printing, a recursive function, and a side-by-side comparison of their time and …

Factorial Program in C – Iterative and Recursive with Output

The factorial program in C is one of the most common exercises for learning recursion and loops. The factorial of a non-negative integer n, written n!, is the product of all positive integers from 1 to n. By definition, 0! = 1. This page covers two approaches — iterative and recursive — with compile-verified code, …

Array search program in C

Very often we encounter a situation where we have to search for a given target value in a list of values. Simple value types like integers are stored in arrays. This program demonstrates how to do a search within an array by using a method called linear search. Linear search, also called as ‘Sequential search’ …

getchar() Function in C — Read a Character with Example

The getchar() function reads a single character from standard input (the keyboard) and returns it. It is one of the simplest input functions in C and a great way to understand how the input buffer works. In this program we use getchar() in a loop to read text entered by the user and count how …

Combinations and Permutations in C (nCr and nPr)

Combinations and permutations in C are computed using two related formulas. A combination C(n, r) counts the number of ways to choose r items from n items where order does not matter. A permutation P(n, r) counts the number of ways to arrange r items chosen from n items where order matters. C(n, r) = …