C++检查字符串是否至少包含1位数字和1个字母

#include <iostream>
#include <string>
#include <cctype>

bool checkString(const std::string& str) {
    bool hasDigit = false;
    bool hasLetter = false;

    for (char c : str) {
        if (std::isdigit(c)) {
            hasDigit = true;
        } else if (std::isalpha(c)) {
            hasLetter = true;
        }

        if (hasDigit && hasLetter) {
            return true;
        }
    }

    return false;
}

int main() {
    std::string str;
    std::cout << "请输入字符串: ";
    std::cin >> str;

    if (checkString(str)) {
        std::cout << "字符串符合要求" << std::endl;
    } else {
        std::cout << "字符串不符合要求" << std::endl;
    }

    return 0;
}