CodeForces Round 991 (Div 3)

CodeForces Round 991 Division 3

Problem A

void solve() {
    std::cin >> n >> m;
    sum = 0, res = 0;
    std::string s[n];
    int len[n], pref[n];
    for (int i = 0; i < n; i++) {
        std::cin >> s[i];
        len[i] = s[i].length();
    }
    if (n == 1) {
        if (len[0] <= m) std::cout << 1 << std::endl;
        else std::cout << 0 << std::endl;
        return;
    }
    pref[0] = len[0];
    if (pref[0] <= m) res++;
    for (int i = 1; i < n; i++) {
        pref[i] = pref[i - 1] + len[i];
        if (pref[i] <= m) {
            res++;
        } else {
            break;
        }
    }
    std::cout << res << std::endl;
}

Problem B

void solve() {
    ll a[200020] = {0};
    ll sum = 0, avg = 0;
    std::cin >> n;
    for (int i = 1; i <= n; i++) {
        std::cin >> a[i];
        sum += a[i];
    }
    if (sum % n != 0) {
        std::cout << "NO" << std::endl;
        return;
    } else {
        avg = sum / n;
    }
    for (int i = 2; i <= n - 1; i++) {
        if (a[i - 1] < avg) {
            a[i + 1] -= (avg - a[i - 1]);
            a[i - 1] = avg;
        } else {
            a[i + 1] += (a[i - 1] - avg);
            a[i - 1] = avg;
        }
    }

    // for (int i = 1; i <= n; i++) {
    //     std::cout << a[i] << " ";
    // }
    // std::cout << std::endl;

    for (int i = 1; i <= n; i++) {
        if (a[i] != avg) {
            std::cout << "NO" << std::endl;
            return;
        }
    }
    std::cout << "YES" << std::endl;
}

Problem C

void solve() {
    std::cin >> s;
    bool res = false;
    int rem = 0, sum = 0, two = 0, three = 0;
    for (int i = 0; i < s.length(); i++) {
        int dgt = s[i] - '0';
        sum += dgt;
        if (dgt == 2) two++;
        if (dgt == 3) three++;
    }

    rem = (9 - sum % 9) % 9; 

    if (rem == 0) {
        std::cout << "YES" << std::endl; 
        return;
    }

    for (int a = 0; a <= two; a++) {
        for (int b = 0; b <= three; b++) {
            int total_increase = 2 * a + 6 * b;
            if (total_increase % 9 == rem) {
                res = true;
                break;
            }
        }
        if (res) break;
    }
    // rem = sum % 9;
    // if (rem == 0) res = true;
    // rem = 9 - rem;
    // if (rem == 0) {
    //     res = true;
    // } else if (rem == 1) { // 1, 10, 19, 28
    //     if (two >= 5) res = true;
    //     if (two >= 2 && three >= 1) res = true;
    // } else if (rem == 2) { // 2, 11, 20, 29, 38, 47, 56
    //     if (two >= 1) res = true;
    // } else if (rem == 3) { // 3, 12, 21
    //     if (two >= 6) res = true;
    //     if (three >= 2) res = true;
    //     if (two >= 3 && three >= 1) res = true;
    // } else if (rem == 4) { // 4, 13, 22
    //     if (two >= 2) res = true;
    // } else if (rem == 5) { // 5, 14, 23, 32
    //     if (two >= 4 && three >= 1) res = true;
    //     if (two >= 1 && three >= 2) res = true;
    // } else if (rem == 6) { // 6, 15, 24, 33
    //     if (three >= 1) res = true;
    //     if (two >= 3) res = true;
    // } else if (rem == 7) { // 7, 16, 25, 34, 43
    //     if (two >= 2 && three >= 2) res = true;
    //     if (two >= 5 && three >= 1) res = true;
    // } else if (rem == 8) { // 8, 17, 26
    //     if (two >= 4) res = true;
    //     if (two >= 1 && three >= 1) res = true;
    // } 

    if (res == true) std::cout << "YES" << std::endl;
    else std::cout << "NO" << std::endl;
}

Problem D

void solve() {
    std::cin >> s;
    int a[200020] = {0};
    for (int i = 1; i <= s.length(); i++) {
        a[i] = s[i - 1] - '0';
        // for (int i = 1; i <= s.length(); i++) std::cout << a[i];
        // std::cout << std::endl;
    }

    for (int i = 2; i <= s.length(); i++) {
        int j = i;
        while (a[j] - 1 > a[j - 1] && j > 1 && a[j] > 0) {
            int tmp = a[j - 1];
            a[j - 1] = a[j] - 1;
            a[j] = tmp;
            j--;
        }
        // for (int i = 1; i <= s.length(); i++) std::cout << a[i];
        // std::cout << std::endl;
    }

    for (int i = 1; i <= s.length(); i++) std::cout << a[i];
    std::cout << std::endl;
}