ofstream*的矢量无法打开任何元素

#include <iostream>
#include <fstream>
#include <vector>

int main() {
    std::vector<std::ofstream*> fileStreams;

    // 创建多个文件流对象并存储在矢量中
    for (int i = 0; i < 5; i++) {
        std::ofstream* fileStream = new std::ofstream("file" + std::to_string(i) + ".txt");
        fileStreams.push_back(fileStream);
    }

    // 逐个打开文件流对象
    for (std::ofstream* fileStream : fileStreams) {
        fileStream->open("file", std::ios::app);
        if (fileStream->is_open()) {
            // 文件打开成功，可以进行写入操作
            *fileStream << "Hello, World!" << std::endl;
            fileStream->close();
        }
    }

    // 清理内存，释放文件流对象
    for (std::ofstream* fileStream : fileStreams) {
        delete fileStream;
    }

    return 0;
}