K&R C Chapter 4 Exercise Solutions — Functions and Program Structure

Chapter 4: Functions and Program Structure is where K&R builds a non-trivial program: a reverse Polish notation (RPN) calculator. The exercises extend it — adding modulo, unary minus, variables, and last-printed-value recall. Other exercises cover recursive printd, recursive itoa, and the C preprocessor. Exercise 4-12 (recursive itoa) and 4-13 (recursive reverse) are elegance tests. These …

C Program to solve equations using Jordan elimination method.

Write a C Program to solve equations using Jordan elimination method.Gauss-Jordan elimination method is used to solve the linear equations. In this method, We find the inverse matrix of the coefficients of equations by elementary row operations. Read more about C Programming Language . and read the C Programming Language (2nd Edition) by K and …

C Program to lock file using semaphores.

Write a C Program to lock file using semaphores.Using semaphores, We can control access to files, shared memory and other things. The basic functionality of a semaphore is that you can either set it, check it, or wait until it clears then set it (“test-n-set”). In C semaphores functions defined in the sys/sem library. Read …

C Program to Encrypt and Decrypt a Password (XOR Cipher)

This classic exercise asks you to encrypt and decrypt a password in C. The right teaching tool for it is the XOR cipher: XOR each character with a key byte, and XOR-ing a second time with the same key restores the original — one function does both directions. This page gives you a tested implementation …

C Program to solve the producer consumer problem

C Program to Solve the Producer-Consumer Problem Using Semaphores The producer-consumer problem (also called the bounded-buffer problem) is a classic process synchronization problem. A producer process generates data items while a consumer process reads them; a semaphore enforces the ordering so the consumer never reads ahead of the producer. Note: This program uses POSIX System …

Round Robin Scheduling in C – Preemptive CPU Algorithm

Round Robin (RR) is a preemptive CPU scheduling algorithm designed for time-sharing systems. Instead of running one process to completion like FCFS, the CPU gives every process a fixed slice of time called a time quantum. If a process doesn’t finish within that slice, it’s paused and moved to the back of the queue, and …