FCFS Scheduling in C – First Come First Served CPU Algorithm

First Come First Served (FCFS) is the simplest CPU scheduling algorithm used by an operating system — processes are executed strictly in the order they arrive, with no interruption once a process starts running. It works exactly like a queue at a ticket counter: whoever arrives first gets served first, and everyone else waits their …

C Program to check matrix is magic square or not

A magic square is a square matrix in which the sum of every row, every column, and both main diagonals is the same number (called the magic constant). This C program reads a square matrix and checks whether it is a magic square. Example: 8 1 6 3 5 7 4 9 2 Every row, …

Delete a File in C – remove() with Error Handling

To delete a file in C, call the standard library function remove() from <stdio.h>: it takes the file name as a string and returns 0 on success. That one line is portable across Linux, macOS, and Windows — no operating-system headers needed. What separates a toy example from production-quality code is what happens when deletion …

Draw a Circle in C — Midpoint Circle Algorithm (No graphics.h)

The classic way this exercise was taught — Turbo C’s <graphics.h> with initgraph() and circle(x, y, r) — hasn’t compiled on a mainstream system in decades: graphics.h was a Borland DOS library, not part of C. But the underlying question is still excellent: how does a computer decide which pixels form a circle? The answer …