What about abandoning global variables and using modern
C++
features and library?
(pass your data file as
stdin
, using input redirection).
#include <iostream>
#include <vector>
#include <string>
#include <sstream>
#include <array>
using namespace std;
using Matrix = vector < vector <int > >;
int main()
{
Matrix m;
string line;
while ( getline( cin, line) )
{
vector <int> row;
istringstream iss(line);
while ( iss )
{
int i;
iss >> i;
row.push_back(i);
}
m.push_back( row );
}
array< array <int, 2>, 4> arr{{{3,0},{2,1},{6,2},{1,1}}};
for ( const auto & a : arr)
{
int r = a[1];
int c = a[0];
cout << "M[" << r << "," << c << "]= " << m[r][c] << "\n";
}
}