Олимпиада ИНФ ТМБ МУП

// 1

#include <iostream>

using namespace std;

int main() {
    int x1, x2, x3, x4, xmx;
    cin >> x1 >> x2 >> x3 >> x4;

    xmx = (x1 + x2 + x3 + x4) / 3;

    if (x1 == xmx)
        cout << x1 - x2 << " " << x1 - x3 << " " << x1 - x4;
    else if (x2 == xmx)
        cout << x2 - x1 << " " << x2 - x3 << " " << x2 - x4;
    else if (x3 == xmx)
        cout << x3 - x1 << " " << x3 - x2 << " " << x3 - x4;
    else
        cout << x4 - x1 << " " << x4 - x2 << " " << x4 - x3;

    return 0;
}

// 2

#include <iostream>

using namespace std;

int main() {
    int N, h = 0;
    cin >> N;
    for (int i = 2; i <= N; i += 3) {
        h++;
        N -= i;
    }
    cout << h;
    return 0;
}

// 3 O(n+q^2)

#include <iostream>

using namespace std;

int main() {

    int n, x, q, m, s = 0;
    cin >> n;
    int a[n + 1];
    for (int i = 1; i <= n; i++) {
        cin >> x;
        a[i] = x;
    }

    cin >> q;

    for (int i = 1; i <= q; i++) {
        cin >> m;
        for (int j = 1; j <= n; j++) {
            if (m >= a[j]) {
                s++;
            }
        }
        cout << s;
        s = 0;
    }

    return 0;
}

// 3 O(n + q)

#include <iostream>

using namespace std;

int main() {

    int n, x, q, m, ma = 0;
    cin >> n;
    int a[n + 1];
    for (int i = 1; i <= n; i++) {
        cin >> x;
        a[x]++;
        ma = max(ma, x);
    }

    for (int i = 0; i < ma; i++) {
        a[i+1] += a[i];
    }

    cin >> q;
    for (int i = 1; i <= q; i++) {
        cin >> m;
        if (m >= ma)
            cout << a[ma] << ' ';
        else
            cout << a[m] << ' ';
    }

    return 0;
}

//4

#include <iostream>

using namespace std;

int main() {
    int n, f;
    bool flag = false;

    cin >> n;
    int a[n + 1];
    for (int i = 1; i <= n; i++) {
        cin >> f;
        a[i] = f;
    }

    for (int i = 1; i <= n; i++) {
        if (a[a[a[i]]] == i) {
            flag = true;
            break;
        }
    }

    if (flag)
        cout << "YES";
    else
        cout << "NO";

    return 0;
}