从源代码本身获取输入C++

#include <iostream>

int main(int argc, char* argv[]) {
    if (argc > 1) {
        std::cout << "输入的参数是：" << argv[1] << std::endl;
    } else {
        std::cout << "未输入参数" << std::endl;
    }
    return 0;
}

#include <iostream>

int main() {
    int input;
    std::cout << "请输入一个整数：";
    std::cin >> input;
    std::cout << "输入的整数是：" << input << std::endl;
    return 0;
}

#include <iostream>
#include <fstream>

int main() {
    std::ifstream inputFile("input.txt");
    if (inputFile.is_open()) {
        int input;
        inputFile >> input;
        std::cout << "从文件中读取的整数是：" << input << std::endl;
        inputFile.close();
    } else {
        std::cout << "无法打开文件" << std::endl;
    }
    return 0;
}