Answer Posted / avinash

#include<pthread.h>
#include<semaphore.h>
#include<stdlib.h>
#include<stdio.h>
#include<malloc.h>
sem_t mutex, cnt;

int readcount = 0;
int rcnt, wcnt;

void *wfun (void *args)
{
sem_wait (&cnt);
printf("\nIn writer : value of read cnt is %d", readcount );
sem_post(&cnt);
}

void *rfun (void *args)
{
sem_wait(&mutex);
readcount ++;
if(readcount == 1)
sem_wait(&cnt);
sem_post(&mutex);
printf("\nIn reader : reader has incremented read cnt, its value is %d",readcount );
sem_wait(&mutex);
readcount --;
if(readcount == 0)
sem_post(&cnt);
sem_post(&mutex);

}

int main()
{

int i, *t;
t = (int*)malloc(sizeof(int));

printf("\nenter number of readers: ");
scanf("%d",&rcnt);
printf("\nenter number of writers: ");
scanf("%d",&wcnt);

//initialize semaphores
sem_init(&mutex,0,1);
sem_init(&cnt,0,1);
pthread_t rdrs[10];
pthread_t wrs[10];

//create reader threads
for(i=0;i<rcnt;i++)
{
*t = i;
pthread_create(&rdrs[i],NULL,rfun, (void *)t);
}

//create writer threads
for(i=0;i<wcnt;i++)
{
*t=i;
pthread_create(&wrs[i],NULL,wfun,(void *)t);
}

for(i=0;i<rcnt;i++)
pthread_join(rdrs[i],NULL);

for(i=0;i<wcnt;i++)
pthread_join(wrs[i],NULL);
return(0);
}

We need to write the function to check the password entered is correct or not based on the following conditions.. a) It must have atleast one lower case character and one digit. b)It must not have any Upper case characters and any special characters c) length should be b/w 5-12. d) It should not have any same immediate patterns like abcanan1 : not acceptable coz of an an pattern abc11se: not acceptable, coz of pattern 11 123sd123 : acceptable, as not immediate pattern adfasdsdf : not acceptable, as no digits Aasdfasd12: not acceptable, as have uppercase character

4454

---

write a program that creates a sequenced array of numbers starting with 1 and alternately add 1 and then 2 to create the text number in the series , as shown below. 1,33,4,6,7,9,............147,148,150 Then , using a binary search , searches the array 100 times using randomly generated targets in the range of 1 to 150

3757

---

write a function that reverse the elements of an array in place.The function must accept only one pointer value and return void.

4563

---

Write a C++ program without using any loop (if, for, while etc) to print prime numbers from 1 to 100 and 100 to 1 (Do not use 200 print statements!!!)

3742

---

create a stucture student containing field for roll no,class,year and marks.create 10 student annd store them in a file

2703

---

write a program to perform generic sort in arrays?

3061

---

Teta-Omeg-Big-Oh Show that f(n) = n2 + 3n3 is ;(n3).

3618

---

output for printf("printf");

2527

---

How can I Draw an ellipse in 3d space and color it by using graph3d?

2611

---

3. Program to find the Sum of give series. a. (1)+(1+2)+(1+2+3)+(1+2+3+4)+……………………………….. b. 1/1+1/9+1/25+1/49+……………...

4929

---

Given a table of the form: Product Sold on A 1/1/1980 B 1/1/1980 C 1/1/1980 A 1/1/1980 B 1/1/1980 C 2/1/1980 A 2/1/1980 There are 30 products and 10,000 records of such type. Also the month period during which sales happened is given to u. Write the program to display the result as: Product Month No. of copies A January 12 A February 15 A March 27 B January 54 B February 15 B March 10 C January 37

2669

---

Write a simple encryption program using string function which apply the substitution method.

6103

---

write a program using 2 D that searches a number and display the number of items 12 inputs values input 15,20, 13, 30, 38, 40,16, 18, 20 ,18 ,20 enter no. to search : 20

3801

---

write a program that prompt the user to enter his height and weight,then calculate the body mass index and show the algorithm used

4848

---

Given a table of the form: Product Sold on A 1/1/1980 B 1/1/1980 C 1/1/1980 A 1/1/1980 B 1/1/1980 C 2/1/1980 A 2/1/1980 There are 30 products and 10,000 records of such type. Also the month period during which sales happened is given to u. Write the program to display the result as: Product Month No. of copies A January 12 A February 15 A March 27 B January 54 B February 15 B March 10 C January 37

2500

---