program mencari luas, konverter suhu dan faktorial C++

#include <iostream.h>
#include <conio.h>
#include <stdio.h>
#include <stdlib.h>
#define phi 3.14

main ()
{
char ulangi;
int n,i,hsl;
        float Kel1, Kel2,Kel3,seg,ling,Luas,P,L,a,b,r,c,d;
int kode;
float suhu, hasil;
char pilihan;
char ulang;

cout<<" ====================================\n";endl;
cout<<" ++++GABUNGAN BEBERAPA PROGRAM++++\n";endl;
cout<<" +++++++++NAMA : MIFTAHUL ILMI++++++++\n";endl;
cout<<" ++++++++++++ NIM  : 1202221+++++++++++\n";endl;
cout<<" ====================================\n\n\n\n";endl;
do
{
system ("cls");
cout<<" ==========================================" << endl;
cout<<"   ||  1. Luas Segi Tiga                                             ||" << endl;
cout<<"   ||  2. persegi panjang                                        ||" << endl;
cout<<"   ||  3. Lingkaran                                                    ||" << endl;
cout<<"   ||  4. Celcius > Reamur > Fahrenhet             ||" << endl;
cout<<"   ||  5. Reamur > Celcius > Fahrenhet             ||" << endl;
cout<<"   ||  6. Fahrenhet > Celcius > Reamur             ||" << endl;
cout<<"   ||  7. Faktorial                                                     ||" << endl;
cout<<" ==========================================" << endl;
cout<<"masukan pilihan anda : ";
cin>>kode;
cout<<endl;

switch (kode)
{

case 1 :

cout<<"Masukan Nilai Alas  :";
    cin>>a;
    cout<<"Masukan Nilai Tinggi  :";
    cin>>b;
    seg = a*b/2;
cout<<"Luas Segi Tiga: "<<seg;break;

case 2:

    cout<<"Masukan Nilai Panjang    : ";
    cin>>P;
    cout<<"Masukan Nilai Lebar      : ";
    cin>>L;
    Luas = P*L;
Kel1 = 2*P+2*L;
cout<<"Luas Persegi panjang: "<<Luas;
cout<<"\nKeliling Persegi panjang: "<<Kel1;break;

case 3:

    cout<<"Masukan Nilai jari-jari   :";
    cin>>r;
    ling = phi*r*r;
Kel3 = 2*phi*r;
    cout<<"Luas Lingkaran: "<<ling;
cout<<"\nKeliling Lingkaran: "<<Kel3;break;


case 4 :

cout << "Masukkan Suhu Dalam Celcius = ";
cin >> suhu ;

hasil = 0.8*suhu ;
cout << "Suhu Dalam Reamur = " << hasil << endl;
hasil = 1.8*suhu+32;
cout << "Suhu Dalam Fahrenheit = " << hasil << endl;

break;

case 5:
cout << "Masukkan Suhu Dalam Reamur = ";
cin >> suhu ;

hasil = 1.25*suhu;
cout << "Suhu Dalam Celcius = " << hasil << endl;
hasil = 2.25*suhu+32;
cout << "Suhu Dalam Fahrenheit = " << hasil << endl;

break;

case 6:
cout << "Masukkan Suhu Dalam Fahrenheit = ";
cin >> suhu ;

hasil = 5*(suhu-32)/9;
cout << "Suhu Dalam Celcius = " << hasil << endl;
hasil = 4*(suhu-32)/9;
cout << "Suhu Dalam Reamur = " << hasil << endl;

break;

case 7 :
cout<< "Menghitung Nilai Faktorial\n" << endl;
cout<< "Masukkan sebuah bilangan : "; cin>> n;

    hsl=1;
for (i=1; i<=n; i++)
hsl= hsl*i;
cout<<"hasil nya adalah = "<<hsl<< endl;


}
getch();
cout<<"\n\napakah anda ingin megulanginya[y/t]:";
cin>>ulangi;
}
while (ulangi=='y'|ulangi=='Y');

getche ();
}