题解 | 凯撒加密

import java.util.Scanner;

// 注意类名必须为 Main, 不要有任何 package xxx 信息
public class Main {
    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        int n = Integer.parseInt(in.nextLine());
        n = n % 26; // 如果n大于26需要取模，保证结果在a到z之间
        String str = in.nextLine();
        char[] chars = new char[str.length()];
        for (int i = 0; i < str.length(); i ++) {
            char c = str.charAt(i);
            if (c + n > 'z') {
                chars[i] = (char)(c + n - 26);
            } else {
                chars[i] = (char)(c + n);
            }
        }
        StringBuilder sb = new StringBuilder();
        for (char c : chars) {
            sb.append(c);
        }
        System.out.println(sb.toString());
    }
}