grupo de permutaciones

#include <iostream>
using namespace std;

int f1 (int a);
int f2 (int a);
int f3 (int a);
int f4 (int a);
int f5 (int a);
int f6 (int a);
string return_type (int a[3]);

int main()
{
    int arr[3];
    string arr2[6][6];

    for (int n=0; n<6; n++)
    {
        for (int m=0; m<6; m++)
        {
            switch (m)
            {
            case 0:
                for (int i=0; i<3; i++)
                    arr[i] = f1(i+1);
                break;
            case 1:
                for (int i=0; i<3; i++)
                    arr[i] = f2(i+1);
                break;
            case 2:
                for (int i=0; i<3; i++)
                    arr[i] = f3(i+1);
                break;
            case 3:
                for (int i=0; i<3; i++)
                    arr[i] = f4(i+1);
                break;
            case 4:
                for (int i=0; i<3; i++)
                    arr[i] = f5(i+1);
                break;
            case 5:
                for (int i=0; i<3; i++)
                    arr[i] = f6(i+1);
                break;
            }

            switch (n)
            {
            case 0:
                for (int i=0; i<3; i++)
                    arr[i] = f1(arr[i]);
                break;
            case 1:
                for (int i=0; i<3; i++)
                    arr[i] = f2(arr[i]);
                break;
            case 2:
                for (int i=0; i<3; i++)
                    arr[i] = f3(arr[i]);
                break;
            case 3:
                for (int i=0; i<3; i++)
                    arr[i] = f4(arr[i]);
                break;
            case 4:
                for (int i=0; i<3; i++)
                    arr[i] = f5(arr[i]);
                break;
            case 5:
                for (int i=0; i<3; i++)
                    arr[i] = f6(arr[i]);
                break;
            }
            arr2[n][m] = return_type(arr);
        }
    }

    cout << " o | f1 f2 f3 f4 f5 f6" << endl;
    cout << "---+---------------------" << endl;
    for (int j=0; j<6; j++)
    {
        cout << 'f' << j+1 << " | ";
        for (int k=0; k<6; k++)
            cout << arr2[j][k] << ' ';
        cout << endl;
    }

    return 0;
}

string return_type (int a[3])
{
    if (a[0]==1 and a[1]==2 and a[2]==3)
        return "f1";
    if (a[0]==1 and a[1]==3 and a[2]==2)
        return "f2";
    if (a[0]==2 and a[1]==1 and a[2]==3)
        return "f3";
    if (a[0]==2 and a[1]==3 and a[2]==1)
        return "f4";
    if (a[0]==3 and a[1]==1 and a[2]==2)
        return "f5";
    if (a[0]==3 and a[1]==2 and a[2]==1)
        return "f6";
    return "error";
}

int f1 (int a)
{
    if (a==1)
        return 1;
    if (a==2)
        return 2;
    if (a==3)
        return 3;
    return 0;
}

int f2 (int a)
{
    if (a==1)
        return 1;
    if (a==2)
        return 3;
    if (a==3)
        return 2;
    return 0;
}

int f3 (int a)
{
    if (a==1)
        return 2;
    if (a==2)
        return 1;
    if (a==3)
        return 3;
    return 0;
}

int f4 (int a)
{
    if (a==1)
        return 2;
    if (a==2)
        return 3;
    if (a==3)
        return 1;
    return 0;
}

int f5 (int a)
{
    if (a==1)
        return 3;
    if (a==2)
        return 1;
    if (a==3)
        return 2;
    return 0;
}

int f6 (int a)
{
    if (a==1)
        return 3;
    if (a==2)
        return 2;
    if (a==3)
        return 1;
    return 0;
}