Tugas Akhir Matematika Diskrit

#include <iostream>
#include <string>
#include <algorithm>
#include <stdlib.h>

using namespace std;
int jumlah = 0;
void logikaPermutasi(string select, string remain){

   if(remain == ""){
        cout << select << endl;
        jumlah++;
        return;
    }
    for(int i=0;remain[i];++i){
        string wk(remain);
        logikaPermutasi(select + remain[i], wk.erase(i, 1));
    }

}

void permutasi(){
    string anagrama;
    cout << "Masukkan sempel kata sandi : ";
    cin >> anagrama;
    if(anagrama.length()>0){
        if(anagrama.length()>=2){
            sort(anagrama.begin(), anagrama.end());
            logikaPermutasi("", anagrama);
            cout << "Jumlah permutasi : " << jumlah << endl;
            system("pause");
        }else{
            cout << "Sempel harus lebih dari 8 karakter" << endl;
            system("pause");
        }
    }else{
        cout << "Masukkan sempel kata sandi" << endl;
        system("pause");
    }
}

int f(int n){
   if (n <= 1){
       cout << "f(" << n << ") = 1" << endl;
       return 1;
   }else{
       cout << "f(" << n << ") = " << n << "*" << "f(" << n-1 << ")"<< endl;
       return n*f(n-1);
   }
}

void fungsi(){
    int angka;
    cout << "Masukkan angka n fungsi : ";
    cin >> angka;
    cout << "RUMUS = f(" << "n" << ") = " << "n" << "*" << "f(" << "n" << "-1)" << endl << endl;
    f(angka);

    int tampung[100];
    int batas=0;
    cout << "\nHasilnya = " << endl;
    int factorial = 1;
    for(int i = 1; i <=angka; ++i)
    {
        factorial *= i;
        tampung[batas] = factorial;
        batas++;
    }

    for(int i=batas-1;i>=0;i--){
        cout << tampung[i] << endl;
    }
    system("pause");
}


int main()
{
    int menu;
    do{
        system("cls");
        cout << "Nama Kelompok : " << endl;
        cout << "1. Khisby Al Ghofari 06.2017.1.06852" << endl;
        cout << "2. M. Ichwan Fanani 06.2017.1.06864 " << endl;
        cout << "3. Ach. Khafid Salim 06.2017.1.06762 " << endl;
        cout << "4. Muchammad Nurdin wahyudi 06.2017.1.06808 " << endl;
        cout << "5. Rizal Arianto  06.2017.1.06798 " << endl << endl;
        cout << "Menu " << endl;
        cout << "1. Kombinasi Kata-Sandi (Permutasi)" << endl;
        cout << "2. Memecahkan Fungsi Rekrusif" << endl;
        cout << "Masukkan menu : ";
        cin >> menu;

        if(menu == 1){
            jumlah = 0;
            permutasi();
        }else if(menu == 2){
            fungsi();
        }else{
            cout << "Menu yang anda maksukkan tidak ada..." << endl;
            system("pause");
        }
    }while(menu != 4);

    return 0;
}