SJF - preemptive

/**
 * author : kaidul
**/
using namespace std;
#include <iostream>
#include <cstdio>
#include <queue>
#include <bitset>

#define M 100

struct process {
    int processId, arrivalTime, burstTime, priority;
    int waitingTime, turnAroundTime, responseTime;
    bool operator < (const process& a) const {
        if(arrivalTime == a.arrivalTime) return burstTime > a.burstTime;
        return arrivalTime > a.arrivalTime;
    }
} pArray[M];

struct waitingProcess {
    int processId, arrivalTime, burstTime, priority;
    bool operator < (const waitingProcess& a) const {
        if(burstTime == a.burstTime) return arrivalTime > a.arrivalTime;
        return burstTime > a.burstTime;
    }
} wp;

priority_queue<process> q;
priority_queue<waitingProcess> waitingList;
bitset <M> taken;

struct timeLine {
    int proc, start, end;
} tmline[M];

int nProcess, timeInterval, averageTime;
float throughtputTime;


int main() {
    freopen("input.txt", "r", stdin);
    cin >> nProcess;

    for (int i = 1; i <= nProcess ; i++) {
        pArray[i].processId = i;
        cin >> pArray[i].arrivalTime >> pArray[i].burstTime >> pArray[i].priority;
        q.push(pArray[i]);
    }
    cin >> timeInterval;

    cout << "Shortest Job First - Preemptive : \n";
    int i = 1;
    process next, top;
    waitingProcess waiting;
    tmline[0].start = 0, tmline[0].proc = 0, tmline[0].end = 0;

    cout << "\nExecution Sequence : \n";
    while (!waitingList.empty() || !q.empty()) {
        tmline[i].start = tmline[i-1].end;
        if(waitingList.empty() && !q.empty()) {
            top = q.top();
            q.pop();
            if(!q.empty()) {
                waitingProcess p;
                next = q.top();
                if(next.arrivalTime < (top.burstTime + tmline[i-1].end)) {
                    tmline[i].end = next.arrivalTime;
                    tmline[i].proc = top.processId;
                    int exeRemain = (top.burstTime + tmline[i-1].end) - next.arrivalTime;
                    p.processId = top.processId, p.arrivalTime = top.arrivalTime, p.priority = top.priority, p.burstTime = exeRemain;
                    waitingList.push(p);
                } else {
                    tmline[i].end = tmline[i].start + top.burstTime;
                    tmline[i].proc = top.processId;
                }

            } else {
                tmline[i].end = tmline[i].start + top.burstTime;
                tmline[i].proc = top.processId;
            }
        } else if(!waitingList.empty() && q.empty()) { // queue khali, waiting list khali na - sobtheke soja case
            waitingProcess wt = waitingList.top();
            tmline[i].end = tmline[i].start + wt.burstTime;
            tmline[i].proc = wt.processId;
            waitingList.pop();
        } else { // both queue have processes
            top = q.top();
            waiting = waitingList.top();
            if(top.burstTime < waiting.burstTime) {
                q.pop();
                if(!q.empty()) {
                    waitingProcess wt;
                    next = q.top();
                    if(next.arrivalTime < (top.burstTime + tmline[i-1].end)) {
                        tmline[i].end = next.arrivalTime;
                        tmline[i].proc = top.processId;
                        int exeRemain = (top.burstTime + tmline[i-1].end) - next.arrivalTime;
                        wt.processId = top.processId, wt.arrivalTime = top.arrivalTime, wt.priority = top.priority, wt.burstTime = exeRemain;
                        waitingList.push(wt);
                    } else {
                        tmline[i].end = tmline[i].start + top.burstTime;
                        tmline[i].proc = top.processId;
                    }

                } else {
                    tmline[i].end = tmline[i].start + top.burstTime;
                    tmline[i].proc = top.burstTime;
                }
            } else { // waitinglist and queue 2ta tei process ase, waiting er tar burst time kom, so se age execute hobe
                q.pop();
                waitingList.pop();
                waitingProcess wt;
                wt.processId = top.processId ,wt.arrivalTime = top.arrivalTime, wt.burstTime = top.burstTime, wt.priority = top.priority;
                waitingList.push(wt);
                tmline[i].end = tmline[i].start + waiting.burstTime;
                tmline[i].proc = waiting.processId;
            }

        }
        cout << tmline[i].start << " " << tmline[i].end << " " << tmline[i].proc << "\n";
        i++;
    }
    cout << "\n";

    taken.reset();
    int range = i -1;

    // calulating response time
    for (int i = 1; i <= range; i++) {
        if(taken.test(tmline[i].proc)) continue;
        pArray[tmline[i].proc].responseTime = tmline[i].start - pArray[tmline[i].proc].arrivalTime;
        taken.set(tmline[i].proc, 1);
    }

    // Calculating Turn-Around Time
    taken.reset();
    for (int i = range; i >= 1; i--) {
        if(taken.test(tmline[i].proc)) continue;
        pArray[tmline[i].proc].turnAroundTime = tmline[i].end - pArray[tmline[i].proc].arrivalTime;
        taken.set(tmline[i].proc, 1);
    }

    // Calculating Waiting Time
    /**
      key: turn-around time = execution(burst) time + waiting time
    **/
    int total = 0;
    for (int i = 1; i <= nProcess; i++ ) {
        pArray[i].waitingTime = pArray[i].turnAroundTime - pArray[i].burstTime;
        cout << pArray[i].processId << "\n";
        cout << "Waiting Time : " << pArray[i].waitingTime << "\n";
        total += pArray[i].waitingTime;
        cout << "TurnAround Time : " << pArray[i].turnAroundTime << "\n";
        cout << "Response Time : " << pArray[i].responseTime << "\n\n";
    }

    averageTime = total / nProcess;
    cout << "Average waiting Time : " << averageTime << "\n";

    throughtputTime = (float)nProcess / tmline[range].end;
    cout << "Throughput Time : " << throughtputTime << "\n";



    return false;
}