Submission #206611

#	Time	Username	Problem	Language	Result	Execution time	Memory
206611		stefdasca	Lutrija (COCI19_lutrija)	C++14	70 / 70	277 ms	504 KiB

lutrija

#include<bits/stdc++.h>
#pragma GCC optimize("O3")
#define fi first
#define se second
#define pb push_back
#define pf push_front
#define mod 1000000007

using namespace std;

typedef long long ll;


int add(int a, int b)
{
    ll x = a+b;
    if(x >= mod)
        x -= mod;
    if(x < 0)
        x += mod;
    return x;
}
ll mul(ll a, ll b)
{
    return (a*b) % mod;
}

ll pw(ll a, ll b)
{
    ll ans = 1;
    while(b)
    {
        if(b & 1)
            ans = (ans * a) % mod;
        a = (a * a) % mod;
        b >>= 1;
    }
    return ans;
}

ll a, b;
bool prim(ll a)
{
    if(a <= 1)
        return 0;
    for(ll i = 2; i * i <= a; ++i)
        if(a % i == 0)
            return 0;
    return 1;
}
int main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    cin >> a >> b;
    if(prim(abs(a - b)))
    {
        cout << 2 << '\n';
        cout << a << " " << b << '\n';
        return 0;
    }
    if(b == 2)
    {
        if(prim(a + 2))
        {
            cout << 3 << '\n';
            cout << a << " " << a+2 << " " << b << '\n';
            return 0;
        }
        if(prim(a - 2))
        {
            cout << 3 << '\n';
            cout << a << " " << a-2 << " " << b << '\n';
            return 0;
        }
        cout << -1;
        return 0;
    }
    if(a == 2)
    {
        if(prim(b + 2))
        {
            cout << 3 << '\n';
            cout << a << " " << b+2 << " " << b << '\n';
            return 0;
        }
        if(prim(b - 2))
        {
            cout << 3 << '\n';
            cout << a << " " << b-2 << " " << b << '\n';
            return 0;
        }
        cout << -1;
        return 0;
    }
    if(prim(a - 2) && prim(b - 2))
    {
        cout << 3 << '\n';
        cout << a << " " << 2 << " " << b << '\n';
        return 0;
    }
    if(prim(a + 2) && prim(b - 2))
    {
        cout << 4 << '\n';
        cout << a << " " << a + 2 << " " << 2 << " " << b << '\n';
        return 0;
    }
    if(prim(a - 2) && prim(b + 2))
    {
        cout << 4 << '\n';
        cout << a << " " << 2 << " " << b + 2 << " " << b << '\n';
        return 0;
    }
    if(prim(a + 2) && prim(b + 2))
    {
        cout << 5 << '\n';
        cout << a << " " << a + 2 << " " << 2 << " " << b + 2 << " " << b << '\n';
        return 0;
    }
    cout << -1;
    return 0;
}

• Subtask 1: 7 / 7
• Subtask 2: 7 / 7
• Subtask 3: 7 / 7
• Subtask 4: 7 / 7
• Subtask 5: 7 / 7
• Subtask 6: 7 / 7
• Subtask 7: 7 / 7
• Subtask 8: 7 / 7
• Subtask 9: 7 / 7
• Subtask 10: 7 / 7