kalkulator sederhana di C++

#include <iostream> using namespace std; unsigned int bil2,bit2; void konversi(unsigned int bil2){ if (bil2>1) { konversi(bil2/2); } bit2 = bil2 % 2; cout<<bit2 << " "; } int main() { int n,m,i,hasil,pil; char menu; do{ system("cls"); cout<<"\n\t======= pilihan =======\n\n"; cout<<"\t1.penjumlahan\n"; cout<<"\t2.perkalian\n"; cout<<"\t3.pembagian\n"; cout<<"\t4.penguranga\n"; cout<<"\t5.pemangkatan\n"; cout<<"\t6.konversi desimal ke biner\n"; cout<<"\n\tinput pilihan :....."; cin>>pil; switch(pil) { case 1: cout<<"\ninput bilangan pertama : "; cin>>n; cout<<"input bilangan kedua : "; cin>>m; hasil = n + m; cout<<"\n"<<"HASIL : "<<n<<" + "<<m<<" = "<<hasil; break; case 2: cout<<"\ninput bilangan pertama : "; cin>>n; cout<<"input bilangan kedua : "; cin>>m; hasil = n * m; cout<<"\n"<<"HASIL : "<<n<<" * "<<m<<" = "<<hasil; break; case 3: cout<<"\ninput bilangan pertama : "; cin>>n; cout<<"input bilangan kedua : "; cin>>m; hasil = n / m; cout<<"\n"<<"HASIL : "<<n<<" / "<<m<<" = "<<hasil; break; case 4: cout<<"\ninput bilangan pertama : "; cin>>n; cout<<"input bilangan kedua : "; cin>>m; hasil = n - m; cout<<"\n"<<"HASIL : "<<n<<" - "<<m<<" = "<<hasil; break; case 5: cout<<"\ninput bilangan pertama : "; cin>>n; cout<<"input bilangan kedua : "; cin>>m; for(i = m;i<=m;i++) { hasil = n; hasil *= n; } cout<<"\n"<<"HASIL : "<<n<<" ^ "<<m<<" = "<<hasil; break; case 6: cout << "Masukkan bilangan desimal : "; cin >> hasil; konversi(hasil); break; default: printf("pilihan tidak ada....!!! coba yang tersdia "); } cout<<"\n\napakah ingin melanjutkan, jika ya tekan Y/y \njika tidak tekan sembarang tombol "; cin>>menu; }while(menu == 'y' || menu == 'Y'); system("pause"); }