Double and long double in g++

The output of the following code is

%x30
                    1.111111111111111164357484e-05
%x30
                    1.111111111111111164357484e-05
%x30
                       0.0000111111112346407026052


but pil is a long double variable and I want it to be printed to higher precision than pid.

How can I do this?

How can I do this using c-style sprintf?

#include<iostream>
#include<iomanip>
#include<typeinfo>
#include<fstream>
#include<string>
#include<stdio.h>
#include<unistd.h>
#include<sys/types.h>
#include<sys/stat.h>
#include<dirent.h>
#include<sys/dirent.h>
#include<fcntl.h>
#include<errno.h>
#include<paths.h>
#include<math.h>

void main(void){
  long double pil=0.000011111111111111111111111111111111111111111111111;
  double pid=pil;
  float pi=pil;

  cout.precision(50);

  string t;
  {
    cout<<"%x30"<<endl;
    char*z=new char[300];
    sprintf(z,"%50.25Lg",pil);
    t=z;
    delete[]z;
    cout<<t<<endl;
  }    
  {
    cout<<"%x30"<<endl;
    char*z=new char[300];
    sprintf(z,"%50.25g",pid);
    delete[]z;
    t=z;
    cout<<t<<endl;
  }    
  {
    cout<<"%x30"<<endl;
    char*z=new char[300];
    sprintf(z,"%50.25f",pi);
    delete[]z;
    t=z;
    cout<<t<<endl;
  }    



}