How can I read graph adjacency information from a text file and store it into a vector in C ?

Reading Graph Adjacency Information from a Text File in C

To read graph adjacency information from a text file and store it into a vector, where each line contains a variable number of integers, we can employ the following steps:

Firstly, we include necessary headers for file manipulation and string streams:

<code class="cpp">#include <fstream>
#include <sstream></code>

Next, we open the text file using an ifstream object:

<code class="cpp">std::ifstream infile("thefile.txt");</code>

We establish a string to store each line:

<code class="cpp">std::string line;</code>

Then, we enter a loop to read each line one by one:

<code class="cpp">while (std::getline(infile, line))</code>

For each line, we create an istringstream to process the string:

<code class="cpp">std::istringstream iss(line);</code>

We declare an integer n and a vector v to store the parsed integers:

<code class="cpp">int n;
std::vector<int> v;</code>

Inside another while loop, we iterate over the istringstream, reading integers into n and pushing them into the vector:

<code class="cpp">while (iss >> n)
{
    v.push_back(n);
}</code>

Finally, we can use the v vector to represent the adjacency information.

The above is the detailed content of How can I read graph adjacency information from a text file and store it into a vector in C ?. For more information, please follow other related articles on the PHP Chinese website!