#include<sys/wait.h>
#include<assert.h>
#include<stdio.h>
#include<stdlib.h>
#include<unistd.h>
#include<fstream>
#include<string.h>
#include<iostream>
#include<cstdlib>

using namespace std;
int main()
{
   int parent_id = getpid();
   int child_id;
   
      
   int n;
   cout<<"Enter number of randoms: ";
   cin>>n;

   char x[n];      // first array to hold the random numbers and send it to first child
   char ch[n];     // second array to the first child to receive the first array
   char ch2[n];    // third array to the second child to receive the array of odd numbers
   
   for(int i=0 ; i<n ; i++)
    {
      x[i] = static_cast<char>((rand()%30)+1);
      cout<<static_cast<int>(x[i])<<"\t";
    }
    cout<<"\n";
   
   int p1[2];   //
   pipe(p1);   // first pipe
   int r =fork();  
   
   if (r == 0)
   {
      waitpid(parent_id,NULL,0);
      
      id1 = getpid();
      
      cout<<"implementation of child 1\n";
      
      close(p1[1]);
      read(p1[0],ch,sizeof(x));  // read the array of random numbers
      
      int x = sizeof(x);
      
      for(int i=0 ; i<x ; i++)
       {
      	 int m = static_cast<int>(ch[i]);
      	 
         if((m % 2) == 0)
          {
           cout<<m<<"\t";
           
           //delet the even number after printing it
           for(int j=i ; j<x-1 ; j++)
           ch[j] = ch[j+1];
           
           x--;
          }
       }
      
      cout<<"\n";
             
      int p2[2];  //
      pipe(p2);  // second pipe inside the first child
      int r2 = fork();
       
       if(r2 == 0)
          { 
            waitpid(child_id,NULL,0);
            
            cout<<"implementation of child 2\n";
         
            close(p2[1]);
            read(p2[0],ch2,sizeof(ch));  // read the odd numbers
            
            for(int i=0 ; i<sizeof(ch2) ; i++)
              cout<<static_cast<int>(ch2[i]);<<"\t";
            
            cout<<"\n";
          }
        
       else
         {
           close(p2[0]);
           write(p2[1],ch,x+1);  // write the odd numbers
           exit(0);
         }

   }
   
   else
     {
       close(p1[0]);
       write(p1[1],x,strlen(x)+1);  // write the array of random numbers to first child
       exit(0);
     }
   
   
   return 0;
}