Permutations and combinations (MATDIS)

#include <iostream>
#include <conio.h>

using namespace std;

class Madis{
public:
void pilih();
void permutasi();
void kombinasi();
private:
int q[100];
};
void Madis::pilih(){
int n;
cout<<"\n1. Permutasi\n2. Kombinasi\n";
cout<<"\n\npilihan anda :";
cin>>n;
if(n==1)permutasi();
if(n==2)kombinasi();
else cout<<"\n\n**selesai***\n\n";
}
void Madis::permutasi(){
int n,N,k,K,p;
N=1;
K=1;
cout<<"\nMasukan nilai n = ";
cin>>n;
cout<<"masukkan nilai r = ";
cin>>k;
if(k>n){
cout<<"\nNilai r harus kurang dari n";
permutasi();
}
p=n-k;
for(int i=1;i<=n;i++){
N=N*i;
}
for(int a=1;a<=p;a++){
K=K*a;
}
cout<<"\Maka hasi Permutasi : "<<N/K;
cout<<"\n\n";
pilih();
}
void Madis :: kombinasi(){
int n,N=1,k,K=1,p,P=1;
cout<<"\nMasukkan nilai n = ";
cin>>n;
cout<<"\nMasukkan nilai r = ";
cin>>k;
if(k>n){
cout<<"\Nilai r harus kurang dari n";
permutasi();
}
p=n-k;
for(int b=1;b<=n;b++){
N=N*b;
}
for(int c=1;c<=k;c++){
K=K*c;
}
for(int d=1;d<=p;d++){
P=P*d;
}
cout<<"\n(n-r)! -> "<<P;
cout<<"\nmaka hasil kombinasi : "<<N/(K*P);
cout<<"\n\n";
pilih();
}
int main(){
Madis z;
z.pilih();
z.permutasi();
z.kombinasi();
system("PAUSE");
return EXIT_SUCCESS;
}