#include <iostream>
#include <unistd.h>
#include <sys/wait.h>
#include <vector>
#include <algorithm>
#include <cstdlib>
#include <ctime>

void random_task(int id) 
{
    srand(time(0));
    int delay = 1 + rand() % 3;

    std::cout << "PID " << getpid()
    << ",PPID " << getppid() 
    << " task " << id
    << " delay " << delay << "s\n";
    sleep(delay);
}

int main()
{


    int total = 6; //tasks
    int levels = 2; //workers
    pid_t root = getpid();
    std::vector<pid_t> pids;
    int worker_id;
    int worker_count = levels;
    // Root spawns children and stores PIDs
    for (int i = 0; i < levels; ++i)
  {
    if(getpid()!=root) {
    break; 
   		       }

pid_t pid = fork();
    if (pid == 0)
               {
    	std::cout << "["<<getpid() << "," << i << std::endl;
        worker_id=i;
        break;
               }
    else
    {
    pids.push_back(pid);
    }
  }
//ROOT REPAIRING LOOP
if(getpid()==root)
{ 
   int status;
  while(1)
   {
   pid_t finished = waitpid(-1,&status, 0);
      if (finished>0)
       { std::cout<<"Reaped PID "<<finished <<"\n";
       pids.erase(std::remove(pids.begin(),pids.end(),finished),pids.end());
       continue;
      }
        if ( finished==-1 && errno ==ECHILD){
       break;
        break;
            }
          }
   }
   else
    {
   //work distribution (modulo)
   for (int i=0;i<total;++i) {
    if(i % worker_count == worker_id) 
     {
      random_task(i);
      }
     }
    }
  return 0;
 
}