#include <iostream> #include <string> int main() { std::string input; std::cout << "请输入四个小写字母: "; std::cin >> input; if (input.length() != 4) { std::cerr << "输入必须包含四个小写字母" << std::endl; return 1; } std::string output; for (char c : input) { if (c >= 'a' && c <= 'z') { if (c == 'z') { output += 'a'; } else { output += c + 1; } } else { std::cerr << "输入必须包含四个小写字母" << std::endl; return 1; } } std::cout << "输出结果: " << output << std::endl; return 0; }