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// Zadatak1 - a
#include<iostream>
using namespace std;
bool prost(int a)
{
    for (size_t i = 2; i < a; i++)
    {
        if (a % i == 0)
            return false;                            
    }
    return true;
}

bool sortiran(int a)
{
    
    while (a)
    {
        if (a % 10 < a / 10 % 10) 
            return false;
        a /= 10;
    }
    return true;
}

int main()
{
    int a;
    while (cout << "unesite broj\t", cin >> a, a < 2 || a>1000);
    for (size_t i = 2; i < a; i++)
    {
        if (prost(i)&&sortiran(i))
            cout << i<<" ";
    }
    cin.get();
    return 0;
}

//Zadatak2 - a
#include<iostream>
using namespace std;
int brojcifara(int a)
{
    int brojac = 0;
    while (a)
    {
        a /= 10;
        brojac++;
    }
    return brojac;
}
bool validan(int a)
{
    while (a)        
    {
        int c = a % 10;
        if (c!= 0 || c!= 1)
            return false;
        a /= 10;                        
    }
    return true;
}
int operacija(int b1, int b2)
{
    int nb = 0, b = 0, brojac=0;
    while (b1) 
    {
        
        int c1 = b1 % 10;
        int c2 = b2 % 10;
        
            if (c1 == c2) b = 1;
            else if (c1 > c2 || c1 < c2)b = 0;
            nb += b * pow(10, brojac);  
            brojac++;
        
        b1 /= 10;
        b2 /= 10;
    }
    return nb;
}
int main()
{
    int nd, b1, b2;
    while (cout << "Unesite ukupan broj cifara\t", cin >> nd, nd <= 0);
    do
    {
        cout << "Unesite b1\t ";
        cin >> b1;
        
    } while (brojcifara(b1)!=nd && validan(b1)==false);
    do
    {
        cout << "Unesite b2\t ";
        cin >> b2;
    } while (brojcifara(b2) != nd && validan(b2)==false);
    cout << "Rezultat " << operacija(b1, b2) << endl;
    cin.get();
    return 0;
}