Answer to Question #279725 in C++ for Aibar

Question

I have project on round robbin scheduling so I want any real life example that is related to round robbin scheduling with c++ source cde

Answer 1

#include <iostream>
#include <algorithm> 
#include <iomanip>
#include <queue> 
using namespace std;

struct process {
    int pid;
    int arrival_time;
    int burst_time;
    int start_time;
    int completion_time;
    int turnaround_time;
    int waiting_time;
    int response_time;
};

bool compare1(process p1, process p2) 
{ 
    return p1.arrival_time < p2.arrival_time;
}

bool compare2(process p1, process p2) 
{  
    return p1.pid < p2.pid;
}

int main() {

    int n;
    int tq;
    struct process p[100];
    float avg_turnaround_time;
    float avg_waiting_time;
    float avg_response_time;
    float cpu_utilisation;
    int total_turnaround_time = 0;
    int total_waiting_time = 0;
    int total_response_time = 0;
    int total_idle_time = 0;
    float throughput;
    int burst_remaining[100];
    int idx;

    cout << setprecision(2) << fixed;

    cout<<"Enter the number of processes: ";
    cin>>n;
    cout<<"Enter time quantum: ";
    cin>>tq;

    for(int i = 0; i < n; i++) {
        cout<<"Enter arrival time of process "<<i+1<<": ";
        cin>>p[i].arrival_time;
        cout<<"Enter burst time of process "<<i+1<<": ";
        cin>>p[i].burst_time;
        burst_remaining[i] = p[i].burst_time;
        p[i].pid = i+1;
        cout<<endl;
    }

    sort(p,p+n,compare1);

    queue<int> q;
    int current_time = 0;
    q.push(0);
    int completed = 0;
    int mark[100];
    memset(mark,0,sizeof(mark));
    mark[0] = 1;

    while(completed != n) {
        idx = q.front();
        q.pop();

        if(burst_remaining[idx] == p[idx].burst_time) {
            p[idx].start_time = max(current_time,p[idx].arrival_time);
            total_idle_time += p[idx].start_time - current_time;
            current_time = p[idx].start_time;
        }

        if(burst_remaining[idx]-tq > 0) {
            burst_remaining[idx] -= tq;
            current_time += tq;
        }
        else {
            current_time += burst_remaining[idx];
            burst_remaining[idx] = 0;
            completed++;

            p[idx].completion_time = current_time;
            p[idx].turnaround_time = p[idx].completion_time - p[idx].arrival_time;
            p[idx].waiting_time = p[idx].turnaround_time - p[idx].burst_time;
            p[idx].response_time = p[idx].start_time - p[idx].arrival_time;

            total_turnaround_time += p[idx].turnaround_time;
            total_waiting_time += p[idx].waiting_time;
            total_response_time += p[idx].response_time;
        }

        for(int i = 1; i < n; i++) {
            if(burst_remaining[i] > 0 && p[i].arrival_time <= current_time && mark[i] == 0) {
                q.push(i);
                mark[i] = 1;
            }
        }
        if(burst_remaining[idx] > 0) {
            q.push(idx);
        }

        if(q.empty()) {
            for(int i = 1; i < n; i++) {
                if(burst_remaining[i] > 0) {
                    q.push(i);
                    mark[i] = 1;
                    break;
                }
            }
        }


    }

    avg_turnaround_time = (float) total_turnaround_time / n;
    avg_waiting_time = (float) total_waiting_time / n;
    avg_response_time = (float) total_response_time / n;
    cpu_utilisation = ((p[n-1].completion_time - total_idle_time) / (float) p[n-1].completion_time)*100;
    throughput = float(n) / (p[n-1].completion_time - p[0].arrival_time);

    sort(p,p+n,compare2);

    cout<<endl;
    cout<<"#P\t"<<"AT\t"<<"BT\t"<<"ST\t"<<"CT\t"<<"TAT\t"<<"WT\t"<<"RT\t"<<"\n"<<endl;

    for(int i = 0; i < n; i++) {
        cout<<p[i].pid<<"\t"<<p[i].arrival_time<<"\t"<<p[i].burst_time<<"\t"<<p[i].start_time<<"\t"<<p[i].completion_time<<"\t"<<p[i].turnaround_time<<"\t"<<p[i].waiting_time<<"\t"<<p[i].response_time<<"\t"<<"\n"<<endl;
    }
    cout<<"Average Turnaround Time = "<<avg_turnaround_time<<endl;
    cout<<"Average Waiting Time = "<<avg_waiting_time<<endl;
    cout<<"Average Response Time = "<<avg_response_time<<endl;
    cout<<"CPU Utilization = "<<cpu_utilisation<<"%"<<endl;
    cout<<"Throughput = "<<throughput<<" process/unit time"<<endl;


}