尝试使用重载运算符读取二进制文件时出现分段错误>>

我正在尝试读取使用以下代码创建的二进制文件：

#include <list>
#include <string>
#include <bitset>
#include <fstream>

struct Node {
  char data;
  int frequency;

  friend std::istream& operator>>(std::istream& input, Node& e) {
    input.read(&e.data, sizeof(e.data));
    input.read(reinterpret_cast<char*>(e.frequency), sizeof(e.frequency));
    return input;
  };

  friend std::ostream& operator<<(std::ostream& output, const Node& e) {
    output.write(&e.data, sizeof(e.data));
    output.write(reinterpret_cast<const char*>(&e.frequency), sizeof(e.frequency));
    return output;
  };
};

int main() {
  std::list<struct Node> list;

  for(char i='a'; i<='z'; i++) {
    struct Node n;
    n.data = i;
    n.frequency = 1;
    list.push_back(n);
  }

  std::string encoded_file = "";

  for(int i=0; i<100; i++) {
    encoded_file = encoded_file + "101010";
  }

  std::fstream output;
  output.open("output.txt", std::ios_base::out | std::ios_base::binary);

  if (output.is_open()) {
    output << list.size();
    for(int i=0; i<list.size(); i++) {
      output << list.front();
      list.pop_front();
    }

    for(long unsigned int i=0; i<encoded_file.length(); i+=8) {
      std::string data = encoded_file.substr(i, 8);
      std::bitset<8> b(data);
      unsigned long x = b.to_ulong();
      unsigned char c = static_cast<unsigned char>( x );
      output << c;
    }
  }

  output.close();

  return 0;
}

此代码似乎工作正常，并且文件output.txt生成没有问题。

但是，当我尝试使用以下代码读取文件时：

#include <list>
#include <string>
#include <bitset>
#include <fstream>
#include <iostream>

struct Node {
  char data;
  int frequency;

  friend std::istream& operator>>(std::istream& input, Node& e) {
    input.read(&e.data, sizeof(e.data));
    input.read(reinterpret_cast<char*>(e.frequency), sizeof(e.frequency));
    return input;
  };

  friend std::ostream& operator<<(std::ostream& output, const Node& e) {
    output.write(&e.data, sizeof(e.data));
    output.write(reinterpret_cast<const char*>(&e.frequency), sizeof(e.frequency));
    return output;
  };
};

int main() {
  std::list<struct Node> list;
  std::string encoded_file = "";

  std::fstream input;
  input.open("output.txt", std::ios_base::in | std::ios_base::binary);

  if (input.is_open()) {
    std::cout << "1" << std::endl;
    int size = 0;
    input >> size;
    std::cout << "size: " << size << std::endl;

    for(int i=0; i<size; i++) {
      Node node;
      input >> node;
      std::cout << node.data << " (" << node.frequency << ")" << std::endl;
      list.push_back(node);
    }
    std::cout << "2" << std::endl;

    char c;
    while(input.get(c)) {
      std::bitset<8> b(c);
      encoded_file = encoded_file + b.to_string();
    }
    std::cout << "3" << std::endl;
  }

  input.close();

  return 0;
}

我得到一个分段错误。当我尝试执行时发生错误input >> node;。我检查了，显然当程序进入时Node::operator>>，e.data被读取，但频率不是。

谁能给我有关如何解决此问题的任何提示？