Round Robin Scheduling Program in C++ : Source Code with Gantt Chart
What is Round Robin Scheduling Algorithm?
Round-robin is basically an operating system concept. Just like the other scheduling algorithms, it is a pre-emptive algorithm which means a task has been temporarily suspended but resumed at a specific process in time. In this algorithm, it forces the process out of the central processing unit when the quota expires. The limited amount of CPU time is called a quantum.
I will give you my own source code for the round robin scheduling program in C++. For I know this is somehow difficult to find in the internet. I used C++ because I am very comfortable with this programming language when it comes to difficult and complex algorithms. My round robin scheduling example with Gantt chart is just simple and straightforward. I added some side details to explain some parts of the code. I hope you would somehow appreciate my imperfect way of coding and help you solve your c++ programming codes problem. By the way, if you are very confused about the process, you could find a simple video explaining this algorithm in youtube. I am not sure if I could be a good teacher using pure words to provide you a round robin algorithm in OS tutorial. A video explanation would definitely help you; don’t have a time though recording one.
Screenshot Results
LEGEND:
AT = Arrival Time
BT = Burst Time
CT = Completion Time
TT = Turnaround Time
WT = Waiting Time
My Source Code of Round Robin Scheduling Algorithm in C++
C++ : Round Robin Scheduling Algorithm
//---www.skellainnovations.com---//
#include<iostream>
#include<conio.h>
using namespace std;
void SearchStack01(int pnt,int tm);
void SearchStack02(int pnt, int tm);
void AddQue(int pnt);
int at[50], bt[50], ct[50]={0}, qt, rqi[50]={0}, c=0, st, flg=0, tm=0, noe=0, pnt=0, btm[50]={0}, tt, wt;
float att, awt;
main(){
cout<<"ROUND ROBIN ALGO : INPUT 5 PROCESSES\n";
for(int x=0;x<5;x++){
cout<<"\nProcess "<<x+1;
cout<<"\nAT=";
cin>>at[x];
cout << "BT=";
cin>>bt[x];
btm[x]=bt[x];}
cout<<"\nEnter time quantum:";
cin>>qt;
system("CLS");
cout<<endl<<"GANTT CHART"<<endl<<at[0];
do{
if(flg==0){
st=at[0];
//---ReduceBT
if(btm[0]<=qt){
tm=st+btm[0];
btm[0]=0;
SearchStack01(pnt,tm);}
else{
btm[0]=btm[0]-qt;
tm=st+qt;
SearchStack01(pnt,tm);
AddQue(pnt);}
}//if
else{
pnt=rqi[0]-1;
st=tm;
//---DeleteQue
for(int x=0;x<noe && noe!=1;x++){
rqi[x]=rqi[x+1];}
noe--;
//---ReduceBT
if(btm[pnt]<=qt){
tm=st+btm[pnt];
btm[pnt]=0;
SearchStack02(pnt, tm);}
else{
btm[pnt]=btm[pnt]-qt;
tm=st+qt;
SearchStack02(pnt, tm);
AddQue(pnt);}
}//else
//AssignCTvalue
if(btm[pnt]==0){
ct[pnt]=tm;
}//if
flg++;
cout<<"]-P"<<pnt+1<<"-["<<tm;
}while(noe!=0);
cout<<"\n\nPROCESS\t AT\t BT\t CT\t TT\t WT\n";
for(int x=0;x<5;x++){
tt=ct[x]-at[x];
wt=tt-bt[x];
cout<<"P"<<x+1<<" \t "<<at[x]<<" \t "<<bt[x]<<" \t "<<ct[x]<<" \t "<<tt<<" \t "<<wt<<"\n";
awt=awt+wt;
att=att+tt;
}//for
cout<<"\nAVERAGE TT: "<<att/5<<"\nAVERAGE WT: "<<awt/5;
}//main
void SearchStack01(int pnt,int tm){
for(int x=pnt+1;x<5;x++){
if(at[x]<=tm){
rqi[noe]=x+1;
noe++;}
}//for
}//void
void SearchStack02(int pnt, int tm){
for(int x=pnt+1;x<5;x++){
//---CheckQue
int fl=0;
for(int y=0;y<noe;y++){
if(rqi[y]==x+1){
fl++;}}
if(at[x]<=tm && fl==0 && btm[x]!=0){
rqi[noe]=x+1;
noe++;}
}//for
}//void
void AddQue(int pnt){
rqi[noe]=pnt+1;
noe++;
}//void
//---www.skellainnovations.com---//
