#include <iostream>
#include<cstdlib>
#include<sys/wait.h>
#include<unistd.h>
int main() {
int pid=fork();
if(pid<0){
    cout<<"error";
}
else if(pid==0){
    cout<<"Parent id :"<<getppid();
    cout<<"\nChild id :"<<getpid();
}
else{
    wait(Null);
    cout<<"parent id :"<<getpid();
}
return 0;
}