diff --git a/cpu_scheduling_algorithms/fcfs_scheduling.cpp b/cpu_scheduling_algorithms/fcfs_scheduling.cpp index 74f1ba64d..21d64498a 100644 --- a/cpu_scheduling_algorithms/fcfs_scheduling.cpp +++ b/cpu_scheduling_algorithms/fcfs_scheduling.cpp @@ -2,17 +2,18 @@ * @file fcfs_scheduling.cpp * @brief Implementation of FCFS CPU scheduling algorithm * @details - * FCFS is a non-preemptive CPU scheduling algorithm in which whichever process arrives first, gets executed first. - * If two or more processes arrive simultaneously, the process with smaller process ID gets executed first. + * FCFS is a non-preemptive CPU scheduling algorithm in which whichever process + * arrives first, gets executed first. If two or more processes arrive + * simultaneously, the process with smaller process ID gets executed first. * @link https://bit.ly/3ABNXOC * @author Pratyush Vatsa(https://github.com/Pratyush219) -*/ + */ -#include // for IO operations -#include // for using vector -#include // for using unordered_set -#include // for priority_queue -#include // for formatting the output +#include // for formatting the output +#include // for IO operations +#include // for priority_queue +#include // for using unordered_set +#include // for using vector using std::cin; using std::cout; @@ -25,30 +26,34 @@ using std::tuple; using std::unordered_set; using std::vector; -/** +/** * @class Compare * @brief Comparator class for priority queue * @tparam S: Data type of Process ID * @tparam T: Data type of Arrival time - * @tparam E: Data type of Burst time -*/ -template -class Compare{ - public: + * @tparam E: Data type of Burst time + */ +template +class Compare { + public: /** * @param t1: first tuple - * @param t2: second tuple - * @brief A comparator function that checks whether to swap the two tuples or not. - * @link Refer https://www.geeksforgeeks.org/comparator-class-in-c-with-examples/ for detailed description of comparator + * @param t2: second tuple + * @brief A comparator function that checks whether to swap the two tuples + * or not. + * @link Refer + * https://www.geeksforgeeks.org/comparator-class-in-c-with-examples/ for + * detailed description of comparator * @returns true if the tuples should be swapped, false othewise - */ - bool operator () (tuple& t1, tuple& t2){ + */ + bool operator()(tuple& t1, + tuple& t2) { // Compare arrival times - if(get<1>(t2) < get<1>(t1)){ + if (get<1>(t2) < get<1>(t1)) { return true; } // If arrival times are same, then compare Process IDs - else if(get<1>(t2) == get<1>(t1)){ + else if (get<1>(t2) == get<1>(t1)) { return get<0>(t2) < get<0>(t1); } return false; @@ -60,10 +65,10 @@ class Compare{ * @brief Class which implements the FCFS scheduling algorithm * @tparam S: Data type of Process ID * @tparam T: Data type of Arrival time - * @tparam E: Data type of Burst time -*/ -template -class FCFS{ + * @tparam E: Data type of Burst time + */ +template +class FCFS { /** * Priority queue of schedules(stored as tuples) of processes. * In each tuple @@ -80,9 +85,10 @@ class FCFS{ schedule; // Stores final status of all the processes after completing the execution. - vector> result; - - // Stores process IDs. Used for confirming absence of a process while adding it. + vector> result; + + // Stores process IDs. Used for confirming absence of a process while adding + // it. unordered_set idList; public: @@ -92,29 +98,34 @@ class FCFS{ * @param arrival: Arrival time of the process * @param burst: Burst time of the process * @returns void - * - */ - void addProcess(S id, T arrival, E burst){ + * + */ + void addProcess(S id, T arrival, E burst) { // Add if a process with process ID as id is not found in idList. - if(idList.find(id) == idList.end()) { - tuple t = make_tuple(id, arrival, burst, 0, 0, 0); + if (idList.find(id) == idList.end()) { + tuple t = + make_tuple(id, arrival, burst, 0, 0, 0); schedule.push(t); idList.insert(id); } } /** - * @brief Algorithm for scheduling CPU processes according to the First Come First Serve(FCFS) scheduling algorithm. - * - * @description FCFS is a non-preemptive algorithm in which the process which arrives first gets executed first. If two or - * more processes arrive together then the process with smaller process ID runs first (each process has a unique proces ID). - * - * I used a min priority queue of tuples to accomplish this task. The processes are ordered by their arrival times. If arrival - * times of some processes are equal, then they are ordered by their process ID. - * + * @brief Algorithm for scheduling CPU processes according to the First Come + * First Serve(FCFS) scheduling algorithm. + * + * @description FCFS is a non-preemptive algorithm in which the process + * which arrives first gets executed first. If two or more processes arrive + * together then the process with smaller process ID runs first (each + * process has a unique proces ID). + * + * I used a min priority queue of tuples to accomplish this task. The + * processes are ordered by their arrival times. If arrival times of some + * processes are equal, then they are ordered by their process ID. + * * @returns void - */ - void scheduleForFcfs(){ + */ + void scheduleForFcfs() { // Variable to keep track of time elapsed so far double timeElapsed = 0; @@ -129,8 +140,9 @@ class FCFS{ // Add Burst time to time elapsed timeElapsed += get<2>(cur); - - // Completion time of the current process will be same as time elapsed so far + + // Completion time of the current process will be same as time + // elapsed so far get<3>(cur) = timeElapsed; // Turnaround time = Completion time - Arrival time @@ -146,27 +158,28 @@ class FCFS{ } /** - * @brief Utility function for printing the status of each process after execution + * @brief Utility function for printing the status of each process after + * execution * @returns void - */ - void printResult(){ - cout << "Status of all the proceses post completion is as follows:" << endl; + */ + void printResult() { + cout << "Status of all the proceses post completion is as follows:" + << endl; - cout << std::setw(17) << left << "Process ID" - << std::setw(17) << left << "Arrival Time" - << std::setw(17) << left << "Burst Time" - << std::setw(17) << left << "Completion Time" - << std::setw(17) << left << "Turnaround Time" - << std::setw(17) << left << "Waiting Time" << endl; - - for(size_t i{}; i < result.size(); i++){ - cout << std::setprecision(2) << std::fixed - << std::setw(17) << left << get<0>(result[i]) - << std::setw(17) << left << get<1>(result[i]) - << std::setw(17) << left << get<2>(result[i]) - << std::setw(17) << left << get<3>(result[i]) - << std::setw(17) << left << get<4>(result[i]) - << std::setw(17) << left << get<5>(result[i]) << endl; + cout << std::setw(17) << left << "Process ID" << std::setw(17) << left + << "Arrival Time" << std::setw(17) << left << "Burst Time" + << std::setw(17) << left << "Completion Time" << std::setw(17) + << left << "Turnaround Time" << std::setw(17) << left + << "Waiting Time" << endl; + + for (size_t i{}; i < result.size(); i++) { + cout << std::setprecision(2) << std::fixed << std::setw(17) << left + << get<0>(result[i]) << std::setw(17) << left + << get<1>(result[i]) << std::setw(17) << left + << get<2>(result[i]) << std::setw(17) << left + << get<3>(result[i]) << std::setw(17) << left + << get<4>(result[i]) << std::setw(17) << left + << get<5>(result[i]) << endl; } } }; @@ -174,20 +187,18 @@ class FCFS{ /** * @brief Entry point of the program * @returns 0 on exit -*/ -int main(){ - FCFS readyQueue; + */ +int main() { + FCFS readyQueue; // Sample test case int n = 3; vector> input = { - make_tuple(1, 0, 30), - make_tuple(2, 0, 5), - make_tuple(3, 0, 5) - }; + make_tuple(1, 0, 30), make_tuple(2, 0, 5), make_tuple(3, 0, 5)}; - for(uint32_t i{}; i < n; i++){ - readyQueue.addProcess(get<0>(input[i]), get<1>(input[i]), get<2>(input[i])); + for (uint32_t i{}; i < n; i++) { + readyQueue.addProcess(get<0>(input[i]), get<1>(input[i]), + get<2>(input[i])); } readyQueue.scheduleForFcfs();