#include <unistd.h>
#include <sys/wait.h>
#include <stdio.h>
int main()
{
  int pid, pid2, pid3;
  pid = fork();

  if( pid  == 0 )//potomny 1
    {
      execl( "d1","", NULL );
      sleep(1000000);
    }
  else
    {
      pid2=fork();
      if(pid2==0)
    {//potomny2
      execl( "d2","", NULL );
      sleep(1000000);
    }
      else
    {
      pid3=fork();
      if(pid3==0)//potomny3
        {
          execl( "d3","", NULL );
          sleep(100000);
        }
      else
        {
          waitpid(pid, NULL, 0);
          waitpid(pid2, NULL, 0);
          waitpid(pid3,NULL, 0);
        }
    }
    }
  //printf("%d %d %d", pid, pid2, pid3);
  // waitpid(pid, NULL, 0);
  //waitpid(pid2, NULL, 0);
  // waitpid(pid3,NULL, 0);
}


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