如何在 C++ 中逐行读取文件中的整数组 [英] How to read groups of integers from a file, line by line in C++

问题描述

我有一个文本文件，每行一个或多个整数，用空格分隔.我怎样才能用 C++ 以优雅的方式阅读这个?如果我不关心行，我可以使用 cin >>，但重要的是在哪一行整数上.

I have a text file with on every line one or more integers, seperated by a space. How can I in an elegant way read this with C++? If I would not care about the lines I could use cin >>, but it matters on which line integers are.

示例输入:

1213 153 15 155
84 866 89 48
12
12 12 58
12

推荐答案

这取决于您是要逐行还是完整地进行.将整个文件转化为一个整数向量:

It depends on whether you want to do it in a line by line basis or as a full set. For the whole file into a vector of integers:

int main() {
   std::vector<int> v( std::istream_iterator<int>(std::cin), 
                       std::istream_iterator<int>() );
}

如果您想在一行一行的基础上进行交易:

If you want to deal in a line per line basis:

int main()
{
   std::string line;
   std::vector< std::vector<int> > all_integers;
   while ( getline( std::cin, line ) ) {
      std::istringstream is( line );
      all_integers.push_back( 
            std::vector<int>( std::istream_iterator<int>(is),
                              std::istream_iterator<int>() ) );
   }
}

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