Pthreads to spawn a child process and print the Fibonacci sequence (http://en.wikipedia.org/wiki/Fibonacci_number) up to a user specified number of places. You do actually have to COMPUTE the sequence, not just print it out from a hardcoded value. ou should divide the sequence roughly in half (if the user inputs an even number, one half - doesn'…

fibopthread.cpp

#include <pthread.h>
#include <stdio.h>
#include <iostream>


using namespace std;

int i, var1, var2;
int inputsize=0;
int fibarray[100];


void *runner (void *param);
int fibfunction(int start, int end);



int main ()
{
    fibarray[0] = 0;
    fibarray[1] = 1;
  
	
    pthread_t tid;
    pthread_attr_t attr;
    int inputsize;
    cout << "Enter number to calculate a Fibonacci sequence" << endl;
    cin >> inputsize;

    pthread_attr_init(&attr);
    int size = inputsize/2;
    pthread_create (&tid, &attr, runner, (void*)&size);
    pthread_join (tid, NULL);
    fibfunction(inputsize/2,inputsize);



    for(i=0; i<inputsize; i++)
    {
        cout << fibarray[i] << endl;
    }

    return 0;
}

void *runner (void *param)
{ 
    int s = *((int*)param);
    fibfunction(2,s);
    pthread_exit(0);
}

int fibfunction(int start, int end)
{
    if(end<=2)
    {
	fibarray[0] = 0;
	fibarray[1] = 1;
    }
    else if(end<=3)
    {
	fibarray[0] = 0;
	fibarray[1] = 1;
	fibarray[2] = 1;
    }
    else{
    var1 = fibarray[start-2];
    var2 = fibarray[start-1];
    for ( i = start; i < end; i++)
    {
        fibarray[i] = var1 + var2;
        var1 = var2;
        var2 = fibarray[i];
    }
    }
    return 0;
}