A polynomial of degree N is an expression of the form: P(x) = ANxN + AN-1xN-1 + … + A1x + A0 The naïve way to evaluate this requires computing each power xk separately, which takes O(N²) multiplications in total. Horner’s method rewrites the polynomial as a nested product that requires only N multiplications and …
C Program to Find Sum and Average of an Array This program reads N integers (positive, negative, and zero) into an array and computes three values: the sum of negatives, the sum of positives, and the average of all elements. Algorithm Read N (array size) from the user. Read N integers into the array one …
The GCD (Greatest Common Divisor) and LCM (Least Common Multiple) of two integers in C are most efficiently found using Euclid’s algorithm. The algorithm repeatedly replaces the larger number with the remainder of dividing the two numbers until the remainder is zero — what remains is the GCD. The LCM then follows from the identity …
Finding all integers in a range that are divisible by a given number is a classic loop exercise. The key tool is the modulo operator % — if i % 7 == 0, then i is exactly divisible by 7 with no remainder. This post shows two programs: one for the classic 100–200 range, and …
Given a list of integers, separate them into two groups — even numbers (divisible by 2) and odd numbers (not divisible by 2) — and report the sum and count of each group. This is a classic array-scanning problem that demonstrates the modulo operator, accumulator variables, and loop-based input. The original post had no code; …
String concatenation in C joins two strings end-to-end into a single result. The standard library provides strcat() for this, but writing it manually teaches how C strings work: they are null-terminated char arrays, and concatenation means walking to the end of the destination string then copying source characters one by one until the null terminator. …