Hovno Kod jak zmrd

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


using namespace std;

int main()
{
    char rodcs[11];
    int rodnecs[10];
    int VelPol = 0;
    int VelPol1 = 0;
    cout << "Zadejte rodne cislo:" << endl;
    cin >> rodcs;

    int delka = strlen(rodcs);

    if (delka != 11)
    {
        cout << "Retezec neni rodnym cislem." << endl;
        return 0;
    }

    if (rodcs[6] != 47)
    {
        cout << "Retezec neni rodnym cislem." << endl;
        return 0;
    }

    for (int i = 0; i < 11; i++)
    {
        if (rodcs[i] != 47)
        {
            rodnecs[i] = rodcs[i] - 48;
        }
    }
    VelPol = rodnecs[0] + rodnecs[2] + rodnecs[4] + rodnecs[7] + rodnecs[9];
    VelPol1 = rodnecs[1] + rodnecs[3] + rodnecs[5] + rodnecs[8] + rodnecs[10];

    int vysledek = VelPol - VelPol1;

    if (vysledek % 11 != 0)
    {
        cout << "Retezec neni rodnym cislem." << endl;
        return 0;
    }
    if (rodnecs[2] == 5 || rodnecs[2] == 6)
    {
        rodnecs[2] = rodnecs[2] - 5;
    }
    if (rodnecs[2] != 0 && rodnecs[2] != 1)
    {
       cout << "Retezec neni rodnym cislem." << endl;
       return 0;
    }
    if (rodnecs[2] == 0)
    {
        if (rodnecs[3] < 1 || rodnecs[3] > 9)
        {
        cout << "Retezec neni rodnym cislem." << endl;
        return 0;
        }
    }
    if (rodnecs[2] == 1)
    {
        if (rodnecs[3] < 0 || rodnecs[3] > 2)
        {
        cout << "Retezec neni rodnym cislem." << endl;
        return 0;
        }
    }
    if (rodnecs[3] == 1 || rodnecs[3] == 3 || rodnecs[3] == 5 || rodnecs[3] == 7 || rodnecs[3] == 8 || rodnecs[3] == 10 || rodnecs[3] == 12)

    {
        if (rodnecs[4] == 0 || rodnecs[4] == 1 || rodnecs[4] == 2 )
        {
            if (rodnecs[5] < 0 || rodnecs[5] > 9)
            {
            cout << "Retezec neni rodnym cislem." << endl;
            return 0;
            }
        }
        if (rodnecs[4] == 3)
        {
            if (rodnecs[5] < 0 || rodnecs[5] > 1)
            {
            cout << "Retezec neni rodnym cislem." << endl;
            return 0;
            }
        }
    }
    if (rodnecs[3] == 4 || rodnecs[3] == 6 || rodnecs[3] == 9 || rodnecs[3] == 11)

    {
        if (rodnecs[4] == 0 || rodnecs[4] == 1 || rodnecs[4] == 2 )
        {
            if (rodnecs[5] < 0 || rodnecs[5] > 9)
            {
            cout << "Retezec neni rodnym cislem." << endl;
            return 0;
            }
        }
        if (rodnecs[4] == 3)
        {
            if (rodnecs[5] != 0)
            {
            cout << "Retezec neni rodnym cislem." << endl;
            return 0;
            }
        }
    }
    if (rodnecs[3] == 2)
    {
        int prevod = 10*rodnecs[0] + rodnecs[1];
        if (prevod % 4 == 0)
        {
            if (rodnecs[4] == 0 || rodnecs[4] == 1 || rodnecs[4] == 2 )
            {
                if (rodnecs[5] < 0 || rodnecs[5] > 9)
                {
                cout << "Retezec neni rodnym cislem." << endl;
                return 0;
                }
            }
        }
        else
        {
            if (rodnecs[4] == 0 || rodnecs[4] == 1)
            {
                if (rodnecs[5] < 0 || rodnecs[5] > 9)
                {
                cout << "Retezec neni rodnym cislem." << endl;
                return 0;
                }
            }
            if (rodnecs[4] == 2 )
            {
                if (rodnecs[5] < 0 || rodnecs[5] > 8)
                {
                cout << "Retezec neni rodnym cislem." << endl;
                return 0;
                }
            }
        }
    }

    cout << "Retezec muze byt rodnym cislem." << endl;

    return 0;
}