fstream如何将两份相似的文件合并

fstream如何将两份相似的文件合并，例如将1.txt和2.txt合并，1.txt和2.txt里面的内容是表格形式，表头一样，内容不一样，如何将其合并，合并后内容连在一起，表头只有一份

1.顺便写了一篇blog. http://blog.csdn.net/infoworld/article/details/46758199

#include <fstream>
#include <string>
#include <iostream>

using namespace std;


//最后一个参数是输出文件.
//支持多余2个的文件合并
//用法,命令行: test.exe 1.txt 2.txt  output.txt
int main(int argc, char const *argv[])
{
    cout << "usage1: test.exe 1.txt 2.txt output.txt" << endl;
    cout << "usage2: test.exe 1.txt 2.txt ... output.txt" << endl;
    if(argc <= 3) return -1;

    bool first_line_readed = false;
    ofstream fout(argv[argc-1], ios::out);
    for(int i = 1 ; i< argc - 1; ++i)
    {
        ifstream fin(argv[i]);
        string str;
        int line_number = 0;
        while(getline(fin,str))
        {
            if(!line_number)
            {
                if(!first_line_readed)
                {
                    first_line_readed = true;
                    str.append("\n");
                    fout.write(str.c_str(),str.size());
                }               
            }else
            {
                str.append("\n");
                fout.write(str.c_str(),str.size());
            }

            line_number++;
        }
    }
    cout << "finish..." << argv[argc-1] << endl;
    return 0;
}