以追加模式写日志文件，指针

log.cpp

#include <iostream>
#include <sstream>
#include <fstream>
using namespace std;

int main()
{
    std::ofstream outfile;
    outfile.open("example.txt", std::ios_base::app); // 以追加模式打开文件

    int* p = new int(15);

    cout << std::hex << p << endl;
    outfile << std::hex << p << std::endl;

    outfile.close();

	return 0;
}