[問題] 格式化寫入檔案錯誤
首先，第一次在PTT上發文，操作還不熟請見諒...
我今年高一，想自學C++
最近在練習fstream的用法
如下
#include <iostream>
#include <fstream>
using namespace std;
int main() {
fstream in;
in.open("test.txt",ios::in);
in.seekg(0,ifstream::end);
long bs = in.tellg();
char* b=new char[bs];
in.seekg(0,ifstream::beg);
in.read(b,bs);
ofstream out;
out.open("test.txt",ios::out);
out.write(b,bs);
out.seekp(0,ofstream::end);
out<<"hello";
out<<endl;
in.close();
out.close();
delete [] b;
return 0;
}
我現在有一個test.txt的檔案
我想要每次執行就寫入一個"hello"到檔案裡
執行第一次很正常:
hello
但執行多次後竟會變這樣:
hello
ihello
hello
hello
第二行第一個字會隨機變亂碼，而且每一行前面會多出一個空格
語法我都是在網路上看來的，寫這個純粹是想要練習
但我改了好幾次都沒辦法成功
久聞PTT高手雲集，新手特來請教......
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