@rool@cpp@Ying_@rn

#include <iostream>
using namespace std;

int main() {
    char ch;
    cin >> ch;

    if (ch >= 'a' && ch <= 'z') {
        cout << "yes" << endl;
    } else {
        cout << "no" << endl;
    }

    return 0;
}

#include <iostream>
#include <vector>
#include <algorithm>

// 计算一个整数的各位数和
int sumOfDigits(int num) {
    int sum = 0;
    while (num > 0) {
        sum += num % 10;
        num /= 10;
    }
    return sum;
}

// 自定义排序函数，首先按各位数和从大到小排序，然后按数字本身从大到小排序
bool customSort(int a, int b) {
    int sumA = sumOfDigits(a);
    int sumB = sumOfDigits(b);

    if (sumA == sumB) {
        return a > b;
    }

    return sumA > sumB;
}

int main() {
    int n;
    std::cin >> n;

    std::vector<int> numbers(n);

    for (int i = 0; i < n; ++i) {
        std::cin >> numbers[i];
    }

    // 使用自定义排序函数进行排序
    std::sort(numbers.begin(), numbers.end(), customSort);

    // 输出排序后的序列
    for (int i = 0; i < n; ++i) {
        std::cout << numbers[i] << " ";
    }
    std::cout << std::endl;

    return 0;
}

#include <iostream>
using namespace std;

int main() {
    char ch;
    cin >> ch;

    if (ch >= 'a' && ch <= 'z') {
        cout << "yes" << endl;
    } else {
        cout << "no" << endl;
    }

    return 0;
}