readData.cpp

#include <iostream>
#include <fstream>
#include <vector>
#include <string>
#include "readData.h"
using namespace std;

vector<vector<int>> read_Data(const int& argc, const char* const* argv) {
  if (argc < 2) {
  cout << "Usage: " << argv[0] << " input_file.extension\n";
  }	

  char p;
  string edge;	
  int vertices, edges;

  // Open the input file
  ifstream File(argv[1]); 

  // Read 'p' and 'edge'
  File >> p >> edge; 

  // Read the number of vertices and the number of edges
  File >> vertices >> edges; 

  vector<vector<int>> G(vertices); 

  char e;
  int u, v;

  while (File >> e) {
      if (e == 'e') {
          // Read an edge (u, v)
          File >> u >> v; 
          // Add v to the adjacency list of u
          G[u-1].emplace_back(v-1); 
          // Add u to the adjacency list of v
          G[v-1].emplace_back(u-1); 
      }
  }

  // Close the input file
  File.close(); 

  /*
  // Print the Graph
  for (int u = 0; u < vertices; u++) {
      cout << u+1 << ": ";
      for (int v : G[u]) {
          cout << v+1 << " ";
      }
      cout << endl;
  }
  */
  return G;
}