小编jro*_*roy的帖子

我刚刚在 macOS Catalina 上安装了 pyenv，并且使用命令收到以下错误消息pyenv doctor：

Cloning /Users/joel.rontynen/.pyenv/plugins/pyenv-doctor/bin/.....
Installing python-pyenv-doctor...
python-build: use readline from homebrew
python-build: use zlib from xcode sdk

BUILD FAILED (OS X 10.15.7 using python-build 20180424)

Inspect or clean up the working tree at /var/folders/tl/_2700jnn5vj0q5ryygn4c4ww0000gp/T/python-build.20201014132428.46509
Results logged to /var/folders/tl/_2700jnn5vj0q5ryygn4c4ww0000gp/T/python-build.20201014132428.46509.log

Last 10 log lines:
checking readline/readline.h, presence... no
checking for readline/readline.h,... no
checking readline/rlconf.h usability... yes
checking readline/rlconf.h presence... yes
checking for readline/rlconf.h... yes
checking for SSL_library_init in -lssl... no
configure: WARNING: OpenSSL <1.1 not installed. …

我正在运行以下程序

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

using namespace std;

int main(int argc, char *argv[])
{
    ifstream input_file(argv[1]);
    vector<string> words;
    string line;

    while(getline(input_file, line))
    {
        cout << line << endl;
        words.push_back(line);
    }
    input_file.close();

    cout << "First and last word: " << words[0] << " " << words.back() << endl;

    return 0;
}

使用以下文本文件作为输入

permission
copper
operation
cop
rationale
rest

我在终端中得到以下输出

permission
copper
operation
cop
rationale
rest

 rest and last word: permission

为什么words.back()在擦除某些文本时将最后一个字打印在行首？