Question

1. Write a C++ program where you implement a synchronized multithreaded version of HAPPY with four threads. The program will take in an array from 1 to n (n = 50) and will be passed to four different threads:

If the current number is divisible by 2, then print HAP

If the current number is divisible by 5, then print PY

If the current number is divisible by both 2 and 5, then print HAPPY

If the number is neither divisible by 2 nor 5, then print the number

• Thread 1 should call csu() to check if divisible by 2 then print HAP.
• Thread 2 should call sb() to check if divisible by 5 then print PY.
• Thread 3 should call csusb() to check if divisible by 2 and 5 then output HAPPY
• Thread 4 should call number() which should only print the numbers.

Example: 1 HAP 3 HAP PY HAP 7 HAP 9 HAPPY 11 HAP 13            HAP PY HAP 17        HAP 19        HAPPY …

Answer 1

#include <iostream> 
#include <thread> 
using namespace std; 
  
// function that will be called by thread first
// it will return HAP if number is divisible by 2
void csu(int value)
{
    if(value%2==0)
    {
        cout<<"HAP";
    }
}
// function that will be called by thread second
// it will return PY if number is divisible by 5
void sb(int value)
{
    if(value%5==0)
    {
        cout<<"PY";
    }
}
// function that will be called by thread third
// it will return HAPPY if number is divisible by 2 as well as 5
void csusb(int value)
{
    if(value%2==0 && value%5==0)
    {
        cout<<"HAPPY";
    }
}
// function that will be called by thread fourth
// it will return a random number between 1-100 if number is neither divisible by 2 nor by 5
void number(int value)
{
    if(value%2!=0 && value%5!=0)
    {
        cout<<(1+rand()%99);
    }
}
  
// main method
int main() 
{ 
    int values[50]; // array of 50 elements
    // loop to store 50 numbers generated randomly using rand() 
    // if you don't want to generate random numbers you can take input from user using cin>>values[i];
    for (int i=0;i<50;i++)
    {
        values[i]=1+rand()%99;// numbers generated will be between 1-100
    }
    // loop to call thread for every element of array
    for(int i=0;i<50;i++)
    {
        thread first (csu,values[i]);   // will call csu(values[i])  
        thread second (sb,values[i]);   // will call sb(values[i])
        thread third (csusb,values[i]); // will call csusb(values[i])
        thread fourth (number,values[i]);   // will call number(values[i])
        first.join();// wait for thread first to finish
        second.join();// wait for thread second to finish
        third.join();// wait for thread third to finish
        fourth.join();// wait for thread fourth to finish
    }
    return 0; 
}