MAXPRIME TS10 PTNK 2018-2019

#define task "MAXPRIME"

#include <iostream>
#include <cstdio>
#include <vector>

using namespace std;

using ll = long long;
using ld = long double;

constexpr int N = 1e5 + 5;
string s;

void Read()
{
    cin >> s;
}

// String to Integer
ll toi(const string &s)
{
    ll ans(0);
    for (auto i : s)
        ans = ans * 10 + i - '0';
    return ans;
}

bool IsPrime(ll v)
{
    if (v == 1)
        return false;
    if (v % 2 == 0) // Số chẵn
        return v == 2;

    for (int i = 3; 1ll * i * i <= v; i += 2)
        if (v % i == 0)
            return false;

    return true;
}

void Solve()
{
    vector<int> p;

    for (int i = 0; i < (int)s.size(); ++i)
        if (s[i] == '?')
            p.emplace_back(i);

    string ans;

    for (int i = 1; i < 10; ++i)
        for (int j = 1; j < 10; ++j)
        {
            s[p[0]] = i + '0';
            s[p[1]] = j + '0';

            if (IsPrime(toi(s)))
                ans = max(ans, s);
        }

    cout << ans;
}

int32_t main()
{
    ios::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
    if (fopen(task ".INP", "r"))
    {
        freopen(task ".INP", "r", stdin);
        freopen(task ".OUT", "w", stdout);
    }

    Read();
    Solve();
}