Can you give a C plus plus program about FCFS algorithm?

Answer 1

#include<iostream.h>

#include<conio.h>

#include<alloc.h>

#include<stdio.h>

struct node

{

char name[10];

int bt;

int wt;

int tat;

struct node*next;

};

typedef struct node n;

n *start=NULL;

void main()

{

int i,m;

n *p,*temp,*t;

clrscr();

cout<<"\nEnter the number of Process:";

cin>>m;

for(i=0;i<m;i++)

{

p=(n*)malloc(sizeof (n));

cout<<"\n\tEnter the Process Name:";

cin>>p->name;

cout<<"\n\tEnter the Burst Time:";

cin>>p->bt;

if(start==NULL)

{

start=p;

start->next=NULL;

start->wt=0;

start->tat=start->bt;

}

else

{

temp=start;

while(temp!=NULL)

{

t=temp;

temp=temp->next;

}

t->next=p;

temp=p;

temp->wt=t->tat;

temp->tat=t->tat+temp->bt;

temp->next=NULL;

}

}

temp=start;

cout<<"\nProcesses\t\tBT\t\tWT\t\tTAT";

while(temp!=NULL)

{

cout<<"\n\t"<<temp->name;

cout<<"\t\t"<<temp->bt;

cout<<"\t\t"<<temp->wt;

cout<<"\t\t"<<temp->tat;

temp=temp->next;

}

cout<<"\n\n Created By:\n\tSanjog";

getch();

}

Answer 2

#include<stdio.h> void main() { int i,ex[20],tr[20],wt[20],n,ar[20]; int j,k,temp,od[20]; float b=0,c=0; printf("\n Enter the number of processes : "); scanf("%d",&n); for(i=0;i<n;i++) { printf(" P%d = ",i+1); printf("\n Excecution time : "); scanf(" %d",&ex[i]); printf("\n Arrival time : "); scanf("%d",&ar[i]); } for(i=0;i<n;i++) od[i]=ar[i]; for(i=0;i<n;i++) for(j=i+1;j<n;j++) { if(ar[i]>ar[j]) { temp=ar[i]; ar[i]=ar[j]; ar[j]=temp; } } for(j=0;j<n;j++) { for(i=0;i<n;i++) { if(ar[j]==od[i]) { if(j==0) { wt[i]=ar[j]; b=wt[i]; tr[i]=ex[i]; c=tr[i]; break; } wt[i]=temp-ar[j]+ar[j-1]; b=b+wt[i]; tr[i]=ex[i]+wt[i]; c=c+tr[i]; break; } } temp=tr[i]; } b=b/n; c=c/n; printf("\n ORDER NAME ARRIVAL-TIME EX.TIME WAITING-TIME TURN-AROUND-TIME \n"); for(j=0;j<n;j++) for(i=0;i<n;i++) { if(ar[j]==od[i]) { printf(" %d P%d\t %d %d\t %d\t\t %d ",j+1,i+1,ar[j],ex[i],wt[i],tr[i]); printf("\n"); break; } } printf("Average waiting time = %f \n Average turn around time = %f \n",b,c); }

.......................................................................................... #include<stdio.h>

#include<string.h>

main()

{

float avgwt,avgtt;

char pname[10][10],c[10][10];

int wt[10],tt[10],bt[10],at[10],t,q,i,n,sum=0,sbt=0,ttime,j,ss=0;

printf("\n\nEnter the number of processes:");

scanf("%d",&n);

printf("\n\n Enter the NAME, BURST TIME and ARRIVAL TIME of thr process");

for(i=0;i<n;i++)

{

printf("\n\nNAME : ");

scanf("%s",&pname[i]);

printf("\n\nBURST TIME : ");

scanf("%d",&bt[i]);

printf("\n\n ARRIVAL TIME :");

scanf("%d",&at[i]);

}

for(i=0;i<n;i++)

for(j=i+1;j<n;j++)

{

if(at[i]>at[j])

{

t=at[i];

at[i]=at[j];

at[j]=t;

q=bt[i];

bt[i]=bt[j];

bt[j]=q;

strcpy(c[i],pname[i]);

strcpy(pname[i],pname[j]);

strcpy(pname[j],c[i]);

}

}

wt[0]=0;

for(i=0;i<n;i++)

{

wt[i+1]=wt[i]+bt[i];

sum=sum+(wt[i+1]-at[i]);

tt[i]=wt[i]+bt[i];

ss=ss+bt[i];

}

avgwt=(float) sum/n;

avgtt=(float) sbt/n;

printf("\n\nAverage waiting time=%f",avgwt);

printf("\n\nAverage turn-around time=%f",avgtt);

printf("\n\n GANTT CHART\n");

for(i=0;i<n;i++)

{printf("|\t%s\t",pname[i]);

}

printf("\n");

for(i=0;i<n;i++)

{

printf("%d\t\t",wt[i]);

}

printf("%d\n",ss);

printf("\n");

}

Answer 3

The First Come First Served algorithm services the first recognized requestor without regard to priority or to length of time required to service that request.

A simple way to do this (there are many ways to do this, some better than others) would be setup an array of flags for a related set of functions. Whenever someone wanted a particular function to run, they would set the corresponding flag. If that is the first flag set, they could just invoke the function. If it is not the first flag set, they must wait. Each function must reset its flag, and then check to see if other flags are set before going to sleep.

You can use a queue construct to make it.The first in,the first out,means you can do FCFS.

Answer 4

#includemain(){int n,a[10],b[10],t[10],w[10],g[10],i,m;float att=0,awt=0; for(i=0;i<10;i++) { a[i]=0; b[i]=0; w[i]=0; g[i]=0; }printf("enter the number of process"); scanf("%d",&n);printf("enter the burst times"); for(i=0;i scanf("%d",&b[i]); printf("\nenter the arrival times"); for(i=0;i scanf("%d",&a[i]); g[0]=0; for(i=0;i<10;i++) g[i+1]=g[i]+b[i]; for(i=0;i { w[i]=g[i]-a[i]; t[i]=g[i+1]-a[i]; awt=awt+w[i]; att=att+t[i]; } awt =awt/n; att=att/n; printf("\n\tprocess\twaiting time\tturn arround time\n"); for(i=0;i { printf("\tp%d\t\t%d\t\t%d\n",i,w[i],t[i]); }printf("the average waiting time is %f\n",awt);printf("the average turn around time is %f\n",att);}

Answer 5

tiger and got