Program C++ untuk mencari KPK dan FPB

#include <iostream>

#include <cstdlib>

#include <windows.h>

using namespace std;

int main (int argc,char*argv)

{

   int i,a,b,r,kpk;

   int p;

   kpk=0;

   cout<<"1. Menentukan KPK"<<endl;

   cout<<"2. Menentukan FPB"<<endl;

   cout<<"3. EXIT"<<endl;

   cout<<"Masukkan Pilihan Anda:";cin>>p;

   system("cls");

   switch (p)

   {

   case 1 :

       {

           cout<<"\n Mencari KPK"<<endl;

           cout<<"masukkan bilangan pertama : ";cin>>a;

           cout<<"masukkan bilangan kedua   : ";cin>>b;

           cout<<endl;

           for(i=1;i<=b;i++)

           {

               kpk=kpk+a;

           if(kpk%b==0)

           {

               cout<<"\n KPK : "<<kpk<<endl;

               break;

           }

           }

       }

   case 2 :

       {

           cout<<"\n Mencari FPB"<<endl;

cout<<"masukkan bilangan pertama : ";cin>>a;

           cout<<"masukkan bilangan kedua   : ";cin>>b;

           r=a%b;

           while (r!=0)

           {

               a=b;

               b=r;

               r=a%b;

           }

           cout<<"\n FPB :"<<b<<endl;

           break;

       }

   case 3 :

       {

           cout<<"EXIT Now!!!"<<endl;

           break;

       }

   default :

       {

           cout<<"Eror!!!"<<endl;

       }

   }

   {

   system("PAUSE");

   return EXIT_SUCCESS;

}

}