A

#include "bits/stdc++.h"

using namespace std;

int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    
    int x;
    cin >> x;
    cout << (x % 2 ? "No" : "Yes") << '\n';
    
    return 0;
}

B

#include "bits/stdc++.h"

using namespace std;

void solve() {
    int x, y;
    cin >> x >> y;

    int z = gcd(x, y);
    cout << (x + z > y && y + z > x ? "Yes" : "No") << '\n';
}

int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    
    int t;
    cin >> t;
    while (t--) {
        solve();
    }
    
    return 0;
}

C

#include "bits/stdc++.h"

using namespace std;

int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    
    int n;
    string s;
    cin >> n >> s;
  
    for (int i = 1; i < n; i++) {
        if (s[i] == s[i - 1]) {
            for (char x : {'r' , 'e', 'd'}) {
                if (x != s[i - 1] && ((i + 1 < n && x != s[i + 1]) || i == n - 1)) {
                    s[i] = x;
                    break;
                }
            }
        }
    }
    cout << s << '\n';
    
    return 0;
}

D

#include "bits/stdc++.h"

using namespace std;

int a[20];

int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    
    int n;
    cin >> n;

    function<void(int, int)> dfs = [&](int n, int i) {
        if (!n) {
            for (int j = 0; j < i; j++) {
                cout << a[j] << " \n"[j == i - 1];
            }
            return;
        }
    
        for (int j = 1; j <= n; j++) {
            if ((i && j != a[i - 1]) || !i) {
                a[i] = j;
                dfs(n - j, i + 1);
                a[i] = 0;
            }
        }
    };

    dfs(n, 0);
    
    return 0;
}

E

#include "bits/stdc++.h"

using namespace std;
using i64 = int64_t;

constexpr int N = 1E6;
int c[N + 1];

int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    
    int n;
    cin >> n;

    vector<int> a(n);
    for (int i = 0; i < n; i++) {
        cin >> a[i];
        c[a[i]]++;
    }

    i64 ans = 0;
    for (int i = 1; i <= N; i++) {
        i64 res = 0;
        for (int j = i; j <= N; j += i) {
            res += i64(j) * c[j];
        }
        ans = max(ans, res * i);
    }
    cout << ans << '\n';

    return 0;
}

F

#include "bits/stdc++.h"

using namespace std;
using i64 = int64_t;

constexpr int P = 998244353;
i64 power(i64 a, i64 b, int p = P) {
    i64 r = 1;
    for (; b > 0; b >>= 1, a = a * a % p) {
        if (b & 1) {
            r = r * a % p;
        }
    }
    return r;
}
i64 inv(i64 a) {
    return power(a, P - 2);
}

int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    
    i64 n;
    cin >> n;

    i64 ans = n % P * 49 % P;
    ans = (ans + (power(10, n) - 1 + P) % P * 40 % P) % P;
    ans = (ans + (power(100, n) - 1 + P) % P * inv(99) % P * 400 % P) % P;
    ans = (ans + (P - (power(10, n) - 1 + P) % P * inv(9) % P * 80 % P)) % P;
    ans = ans * inv(81) % P;
    cout << ans << '\n';
    
    return 0;
}