After lots of research online and studying various source codes. I thought of trying myself to come up with a way to write the round robin code.
I tried but i get errors in certain part of my output. I am unable to generate the Gaint chart and also please can anyone explain me where i made mistake in calculating my waiting time algorithm.
Can anyone explain me specially how can i get the waiting time of each process and kindly correct my algorithm .Please i have a sincere request. I am a self learner and there is basically no one other than online articles or books to help me understand a code. So, if you correct my mistake, please can you explain me along with the correction. I really want to get the concept because i don't want to do the same mistake again. Thanks.
------- Here is my code --------------
#include<iostream>
using namespace std;
int main()
{
int k,j,q,i,n,ts,temp;
int aw; float awt;
int bt[10],wt[10],te[10],rt[10],at[10];j=0; //te array stores the number of times a process comes to CPU before completion
//bt is my burst time store array
//wt is my waiting time array
//te keeps a count of the number of times a process enters the CPU before completion
//at is the arrival time
cout<<"Enter number of processes"<<endl;
cin>>n;
for(i=0;i<n;i++)
{
cout<<"Enter burst time"<<endl;
cin>>bt[i];
cout<<"Enter arrival times"<<endl;
cin>>at[i];
te[i] = 0; wt[i] = 0;
}
for(i=0;i<n;i++)
{
for(j = i+1;j<n;j++)
{
if(at[j]<at[i])
{
temp = at[i];
at[i] = at[j];
at[j] = temp;
if(at[j] ==at[i])
temp = bt[i];
bt[i] = bt[j];
bt[j] = temp;
}
}
}
cout<<"Enter time slice"<<endl;
cin>>ts;
cout<<"process:"<<endl;
for(i=0;i<n;i++)
{
cout<<"\t"<<i+1<<endl;
}
cout<<"Burst time:"<<endl;
for(i=0;i<n;i++)
{
cout<<" "<<bt[i]<<endl;
rt[i] = bt[i];
}
cout<<"arrival time:"<<endl;
for(i=0;i<n;i++)
{
cout<<" "<<at[i]<<endl;
}
cout<<"Gaint chart"<<endl;
while (j<=n)
{
j++;
for(i = 0;i<n;i++)
{
if(rt[i] ==0) continue;
if(rt[i]>=ts)
{
cout<<"\t"<<q<<i+1<<endl;
q = q + ts;
rt[i] = rt[i] - ts;
te[i] = te[i] + 1;
}
else
{
cout<<" "<<q<<i+1<<endl;
wt[i] = q-te[i]*ts;
q = q +rt[i];
rt[i] = rt[i] - rt[i];
}
}
}
awt = 0;
cout<<"Process Waiting Time"<<endl;
for(i =0;i<n;i++)
{
wt[i] = wt[i] - at[i];
cout<<" "<<i+1<<endl;
cout<<wt[i]<<endl;
awt = awt + wt[i];
}
aw = awt;
cout<<"Total waiting time"<<aw<<endl;
cout<<"Average waiting time "<<awt/n<<endl;
return 0;
}
