Code:
#include <stdio.h>
int main() {
int n, i;
float num[100], sum = 0.0, avg;
clrscr();
printf("Enter the numbers of elements: ");
scanf("%d", &n);
while (n > 100 || n < 1) {
printf("Error! number should in range of (1 to 100).\n");
printf("Enter the number again: ");
scanf("%d", &n);
}
for (i = 0; i < n; ++i) {
printf("%d. Enter Marks: ", i + 1);
scanf("%f", &num[i]);
sum += num[i];
}
avg = sum / n;
printf("Average = %.2f", avg);
getch();
return 0;
}
Output:
Code:
#include <stdio.h>
#include <conio.h>
int main(){
int A[100][4];
int i, j, n, total = 0, index, temp;
float avg_wt, avg_tat;
clrscr();
printf("Enter number of process: ");
scanf("%d", &n);
printf("Enter Burst Time:\n");
for (i = 0; i < n; i++) {
printf("P%d: ", i + 1);
scanf("%d", &A[i][1]);
A[i][0] = i + 1;
}
for (i = 0; i < n; i++) {
index = i;
for (j = i + 1; j < n; j++)
if (A[j][1] < A[index][1])
index = j;
temp = A[i][1];
A[i][1] = A[index][1];
A[index][1] = temp;
temp = A[i][0];
A[i][0] = A[index][0];
A[index][0] = temp;
}
A[0][2] = 0;
for (i = 1; i < n; i++) {
A[i][2] = 0;
for (j = 0; j < i; j++)
A[i][2] += A[j][1];
total += A[i][2];
}
avg_wt = (float)total / n;
total = 0;
printf("P
BT
WT
TAT\n");
for (i = 0; i < n; i++) {
A[i][3] = A[i][1] + A[i][2];
total += A[i][3];
printf("P%d
%d
%d
%d\n", A[i][0],
A[i][1], A[i][2], A[i][3]);
}
avg_tat = (float)total / n;
printf("Average Waiting Time= %f", avg_wt);
printf("\nAverage Turnaround Time= %f", avg_tat);
getch();
return(0);
}
Output:
Code:
#include<stdio.h>
#include<conio.h>
int main()
{
int n,bt[20],wt[20],tat[20],avwt=0,avtat=0,i,j;
clrscr();
printf("Enter total number of processes(maximum 20):");
scanf("%d",&n);
printf("\nEnter Process Burst Time\n");
for(i=0;i<n;i++)
{
printf("P[%d]:",i+1);
scanf("%d",&bt[i]);
}
wt[0]=0;
//waiting time for first process is 0
//calculating waiting time
for(i=1;i<n;i++)
{
wt[i]=0;
for(j=0;j<i;j++)
wt[i]+=bt[j];
}
printf("\nProcess\t\tBurst Time\tWaiting Time\tTurnaround Time");
//calculating turnaround time
for(i=0;i<n;i++)
{
tat[i]=bt[i]+wt[i];
avwt+=wt[i];
avtat+=tat[i];
printf("\nP[%d]\t\t%d\t\t%d\t\t%d",i+1,bt[i],wt[i],tat[i]);
}
avwt/=i;
avtat/=i;
printf("\n\nAverage Waiting Time:%d",avwt);
printf("\nAverage Turnaround Time:%d",avtat);
getch();
return 0;
}
Output:
Code:
#include<stdio.h>
#include<conio.h>
void main()
{
int et[30],ts,n,i,x=0,tot=0;
char pn[10][10];
clrscr();
printf("Enter the no of processes:");
scanf("%d",&n);
printf("Enter the time quantum:");
scanf("%d",&ts); for(i=0;i<n;i++)
{
printf("enter process name & estimated time:");
scanf("%s %d",pn[i],&et[i]);
}
printf("The processes are:");
for(i=0;i<n;i++)
printf("process %d: %s\n",i+1,pn[i]);
for(i=0;i<n;i++)
tot=tot+et[i];
while(x!=tot)
{
for(i=0;i<n;i++)
{
if(et[i]>ts)
{
x=x+ts;
printf("\n %s -> %d",pn[i],ts);
et[i]=et[i]-ts;
}
else if((et[i]<=ts)&&et[i]!=0)
{
x=x+et[i];
printf("\n %s -> %d",pn[i],et[i]); et[i]=0;}
}
}
printf("\n Total Estimated Time:%d",x);
getch();
}
Output:
Code:
#include<stdio.h>
#include<conio.h>
int main()
{
int bt[20],p[20],wt[20],tat[20],pr[20],i,j,n,total=0,pos,temp,avg_wt,avg_tat;
clrscr();
printf("Enter Total Number of Process:");
scanf("%d",&n);
printf("\nEnter Burst Time and Priority\n");
for(i=0;i<n;i++)
{
printf("\nP[%d]\n",i+1);
printf("Burst Time:");
scanf("%d",&bt[i]);
printf("Priority:");
scanf("%d",&pr[i]);
p[i]=i+1;
}
for(i=0;i<n;i++)
{
pos=i;
for(j=i+1;j<n;j++)
{
if(pr[j]<pr[pos])
pos=j;
}
temp=pr[i];
pr[i]=pr[pos];
pr[pos]=temp;
temp=bt[i];
bt[i]=bt[pos];
bt[pos]=temp;
temp=p[i];
p[i]=p[pos];
p[pos]=temp;
}
wt[0]=0;
for(i=1;i<n;i++)
{
wt[i]=0;
for(j=0;j<i;j++)
wt[i]+=bt[j];
total+=wt[i];
}
avg_wt=total/n;
total=0;
printf("\nProcess\t
Burst Time
\tWaiting Time\tTurnaround Time");
for(i=0;i<n;i++)
{
tat[i]=bt[i]+wt[i];
total+=tat[i];
printf("\nP[%d]\t\t %d\t\t
}
%d\t\t\t%d",p[i],bt[i],wt[i],tat[i]);
avg_tat=total/n;
printf("\n\nAverage Waiting Time=%d",avg_wt);
printf("\nAverage Turnaround Time=%d\n",avg_tat);
getch();
return 0;
}
Output:
Code:
#include<semaphore.h>
#include<stdio.h>
#include<stdlib.h>
#include<pthread.h>
#include<string.h>
sem_t x,y;
pthread_t tid;
pthread_t writerthreads[100],readerthreads[100];
int readercount;
void *reader(void* param)
{
sem_wait(&x);
readercount++;
if(readercount==1)
sem_wait(&y);
sem_post(&x);
printf("\n%d reader is inside",readercount);
sem_wait(&x);
readercount--;
if(readercount==0)
{
sem_post(&y);
}
sem_post(&x);
printf("\n%d Reader is leaving",readercount+1);
}
void *writer(void* param)
{
printf("\nWriter is trying to enter");
sem_wait(&y);
printf("\nWriter has entered");
sem_post(&y);
printf("\nWriter is leaving");
}
int main()
{
int n2,i;
printf("Enter the number of readers:");
scanf("%d",&n2);
int n1[n2];
sem_init(&x,0,1);
sem_init(&y,0,1);
for(i=0;i<n2;i++)
{
pthread_create(&writerthreads[i],NULL,reader,NULL);
pthread_create(&readerthreads[i],NULL,writer,NULL);
}
for(i=0;i<n2;i++)
{
pthread_join(writerthreads[i],NULL);
pthread_join(readerthreads[i],NULL);
}
return (0);
}
Output:
Code:
#include <stdio.h>
#include <conio.h>
int current[5][5], maximum_claim[5][5], available[5];
int allocation[5] = {0, 0, 0, 0, 0};
int maxres[5], running[5], safe = 0;
int counter = 0, i, j, exec, resources, processes, k = 1;
int main()
{
clrscr();
printf("\nEnter number of processes: ");
scanf("%d", &processes);
for (i = 0; i < processes; i++)
{
running[i] = 1;
counter++;
}
printf("\nEnter number of resources: ");
scanf("%d", &resources);
printf("\nEnter Claim Vector:");
for (i = 0; i < resources; i++)
{
scanf("%d", &maxres[i]);
}
printf("\nEnter Allocated Resource Table:\n");
for (i = 0; i < processes; i++)
{
for(j = 0; j < resources; j++)
{
scanf("%d", &current[i][j]);
}
}
printf("\nEnter Maximum Claim Table:\n");
for (i = 0; i < processes; i++)
{
for(j = 0; j < resources; j++)
{
scanf("%d", &maximum_claim[i][j]);
}
}
printf("\nThe Claim Vector is: ");
for (i = 0; i < resources; i++)
{
printf("\t%d", maxres[i]);
}
printf("\nThe Allocated Resource Table:\n");
for (i = 0; i < processes; i++)
{
for (j = 0; j < resources; j++)
{
printf("\t%d", current[i][j]);
}
printf("\n");
}
printf("\nThe Maximum Claim Table:\n");
for (i = 0; i < processes; i++)
{
for (j = 0; j < resources; j++)
{
printf("\t%d", maximum_claim[i][j]);
}
printf("\n");
}
for (i = 0; i < processes; i++)
{
for (j = 0; j < resources; j++)
{
allocation[j] += current[i][j];
}
}
printf("\nAllocated resources:");
for (i = 0; i < resources; i++)
{
printf("\t%d", allocation[i]);
}
for (i = 0; i < resources; i++)
{
available[i] = maxres[i] - allocation[i];
}
printf("\nAvailable resources:");
for (i = 0; i < resources; i++)
{
printf("\t%d", available[i]);
}
printf("\n");
while (counter != 0)
{
safe = 0;
for (i = 0; i < processes; i++)
{
if (running[i])
{
exec = 1;
for (j = 0; j < resources; j++)
{
if (maximum_claim[i][j] - current[i][j] > available[j])
{
exec = 0;
break;
}
}
if (exec)
{
printf("\nProcess%d is executing\n", i + 1);
running[i] = 0;
counter--;
safe = 1;
for (j = 0; j < resources; j++)
{
available[j] += current[i][j];
}
break;
}
}
}
if (!safe)
{
printf("\nThe processes are in unsafe state.\n");
break;
}
else
{
printf("\nThe process is in safe state");
printf("\nAvailable vector:");
for (i = 0; i < resources; i++)
{
printf("\t%d", available[i]);
}
printf("\n");
}
}
getch();
return 0;
}
Output:
Code:
#include<stdio.h>
#include<conio.h>
int main()
{
int i,j,n,a[50],frame[10],no,k,avail,count=0;
clrscr();
printf("\n ENTER THE NUMBER OF PAGES:\n");
scanf("%d",&n);
printf("\n ENTER THE PAGE NUMBER :\n");
for(i=1;i<=n;i++)
scanf("%d",&a[i]);
printf("\n ENTER THE NUMBER OF FRAMES :");
scanf("%d",&no);
for(i=0;i<no;i++)
frame[i]= -1;
j=0;
printf("\tref string\t page frames\n");
for(i=1;i<=n;i++)
{
printf("%d\t\t",a[i]);
avail=0;
for(k=0;k<no;k++)
if(frame[k]==a[i])
avail=1;
if (avail==0)
{
frame[j]=a[i];
j=(j+1)%no;
count++;
for(k=0;k<no;k++)
printf("%d\t",frame[k]);
}
printf("\n");
}
printf("Page Fault Is %d",count);
getch();
return 0;
}
Output:
Code:
#include<stdio.h>
#include<conio.h>
void main()
{
int q[20],p[50],c=0,c1,d,f,i,j,k=0,n,r,t,b[20],c2[20];
clrscr();
printf("Enter no of pages:");
scanf("%d",&n);
printf("Enter the reference string:");
for(i=0;i<n;i++)
scanf("%d",&p[i]);
printf("Enter no of frames:");
scanf("%d",&f);
q[k]=p[k];
printf("\n\t%d\n",q[k]);
c++;
k++;
for(i=1;i<n;i++)
{
c1=0;
for(j=0;j<f;j++)
{
if(p[i]!=q[j])
c1++;
}
if(c1==f)
{
c++;
if(k<f)
{
q[k]=p[i];
k++;
for(j=0;j<k;j++)
printf("\t%d",q[j]);
printf("\n");
}
else{
for(r=0;r<f;r++)
{
c2[r]=0;
for(j=i-1;j<n;j--)
{
if(q[r]!=p[j])
c2[r]++;
else
break;
}
}
for(r=0;r<f;r++)
b[r]=c2[r];
for(r=0;r<f;r++)
{
for(j=r;j<f;j++)
{
if(b[r]<b[j])
{
t=b[r];
b[r]=b[j];
b[j]=t;
}
}
}
for(r=0;r<f;r++)
{
if(c2[r]==b[0])
q[r]=p[i];
printf("\t%d",q[r]);
}
printf("\n");
}
}
}
printf("\nThe no of page faults is %d",c);
getch();
}
Output:
Code:
#include<stdio.h>
#include<conio.h>
void main()
{
int bsize[10], psize[10], bno, pno, flags[10], allocation[10], i, j;
clrscr();
for(i = 0; i < 10; i++)
{
flags[i] = 0;
allocation[i] = -1;
}
printf("Enter no. of blocks: ");
scanf("%d", &bno);
printf("\nEnter size of each block: ");
for(i = 0; i < bno; i++)
scanf("%d", &bsize[i]);
printf("\nEnter no. of processes: ");
scanf("%d", &pno);
printf("\nEnter size of each process: ");
for(i = 0; i < pno; i++)
scanf("%d", &psize[i]);
for(i = 0; i < pno; i++)
for(j = 0; j < bno; j++)
if(flags[j] == 0 && bsize[j] >= psize[i])
{
allocation[j] = i;
flags[j] = 1;
break;
}
//display allocation details
printf("\nBlock no.\tBlock size\t\tprocess no.\t\tFile size");
for(i = 0; i < bno; i++)
{
printf("\n%d\t\t%d\t\t", i+1, bsize[i]);
if(flags[i] == 1)
printf("%d\t\t\t%d",allocation[i]+1,psize[allocation[i]]);
else
printf("Not allocated");
}
getch();
}
Output:
Code:
#include<stdio.h>
#include<conio.h>
void main()
{
int fragment[20],b[20],p[20],i,j,nb,np,temp,lowest=9999;
static int barray[20],parray[20];
clrscr();
printf("\n\t\t\tMemory Management Scheme - Best Fit");
printf("\nEnter the number of blocks:");
scanf("%d",&nb);
printf("Enter the number of processes:");
scanf("%d",&np);
printf("\nEnter the size of the blocks:-\n");
for(i=1;i<=nb;i++) {
printf("Block no.%d:",i);
scanf("%d",&b[i]);
}
printf("\nEnter the size of the processes :-\n");
for(i=1;i<=np;i++){
printf("Process no.%d:",i);
scanf("%d",&p[i]);
}
for(i=1;i<=np;i++){
for(j=1;j<=nb;j++){
if(barray[j]!=1){
temp=b[j]-p[i];
if(temp>=0)
if(lowest>temp)
{
parray[i]=j;
lowest=temp;
}
}
}
fragment[i]=lowest;
barray[parray[i]]=1;
lowest=10000;
}
printf("\nProcess_no\tProcess_size\tBlock_no\tBlock_size\tFragment");
for(i=1;i<=np && parray[i]!=0;i++)
printf("\n%d\t\t%d\t\t%d\t\t%d\t\t%d",i,p[i],parray[i],b[parray[i]],fragment[i]);
getch();
}
Output:
Code:
#include<stdio.h>
#include<conio.h>
#define max 25
void main()
{
int frag[max],b[max],f[max],i,j,nb,nf,temp,highest=0;
static int bf[max],ff[max];
clrscr();
printf("\n\tMemory Management Scheme - Worst Fit");
printf("\nEnter the number of blocks:");
scanf("%d",&nb);
printf("Enter the number of files:");
scanf("%d",&nf);
printf("\nEnter the size of the blocks:-\n");
for(i=1;i<=nb;i++)
{
printf("Block %d:",i);
scanf("%d",&b[i]);
}
printf("Enter the size of the files :-\n");
for(i=1;i<=nf;i++)
{
printf("File %d:",i);
scanf("%d",&f[i]);
}
for(i=1;i<=nf;i++)
{
for(j=1;j<=nb;j++)
{
if(bf[j]!=1)
//if bf[j] is not allocated
{
temp=b[j]-f[i];
if(temp>=0)
if(highest<temp)
{
ff[i]=j;
highest=temp;
}
}
frag[i]=highest;
bf[ff[i]]=1;
highest=0;
}
ff[i]=j;
highest=temp;
}
printf("\nFile_no:\tFile_size :\tBlock_no:\tBlock_size:\tFragement");
for(i=1;i<=nf;i++)
printf("\n%d\t\t%d\t\t%d\t\t%d\t\t%d",i,f[i],ff[i],b[ff[i]],frag[i]);
getch();
}
Output:
Code:
#include<stdio.h>
#include<unistd.h>
#include<string.h>
void main()
{
int p1[2],p2[2],p3[2],p4[2];
int i,j=0,k=0,l=0;
char r[10],s[10],t[10],u[10];
printf("\t PROCESS 1.ENTER THE STRING :");
scanf("%s",r);
pipe(p1);
pipe(p2);
write(p1[1],r,sizeof(r));
write(p2[1],r,sizeof(r));
int a=fork();
if(a==0)
{
printf("\n\t PROCESS 2:it splits the given string\n");
read(p1[0],r,sizeof(r));
int n=strlen(r);
for(i=0;i<n/2;i++)
{
s[i]=r[i];
}
for(i=n/2;i<=n;i++)
{
t[j++]=r[i];
}
pipe(p3);
pipe(p4);
write(p3[1],s,sizeof(s));
write(p4[1],t,sizeof(t));
int b=fork();
if(b==0)
{
printf("p4 %d\t",getpid());
printf("p2 %d\n",getppid());
read(p3[0],s,sizeof(s));
printf("\t PROCESS 4:sub string \t %s \t",s);
printf("no of char=%d \n",strlen(s));
}
else
{
int c=fork();
if(c==0)
{
printf("p5 %d\t",getpid());
printf("p2 %d\n",getppid());
read(p4[0],t,sizeof(t));
printf("\t PROCESS 5:sub string \t %s \t",t);
printf("no of char=%d \n",strlen(t));
}
else
{
wait();
printf("p2 %d\t",getpid());
printf("p1 %d\n",getppid());
} }}
else
{
wait();
int d=fork();
if(d==0)
{
printf("p3 %d\t",getpid());
printf("p1 %d\n",getppid());
read(p2[0],r,sizeof(r));
for(i=strlen(r)-1;i>=0;i--)
{
u[l++]=r[i];
}
for(i=0;i<strlen(r);i++)
{
if(u[i]==r[i])
k++;
else
continue;
}
if(k==strlen(r))
printf("\t PROCESS 3: the given string is palindrome\n");
else
printf("\t PROCESS 3: the given string is not palindrome\n");
}
else
{
printf("p1 %d\t",getpid());
printf("kernal %d\t\n",getppid());
}
}
}
Output: