I’m currently working on a problem that takes 2 matrix as its input.
I notice that when I use the same ifstream object to open 2 file, values of the second file get weird when I print it out.
This is not the case if I use the second ifstream object to take the input. I wanted to know what is happening and why can’t I use just one.
`
int main(){
ifstream fin;

int G[20][20];
int G2[20][20];
int n = 8;

fin.open("inMat1.txt");
for (int i = 0; i < n; i++)
    for (int j = 0; j < n; j++)
      fin >> G[i][j];


fin.open("inMat2.txt");
for (int i = 0; i < n; i++)
    for (int j = 0; j < n; j++)
      fin >> G2[i][j];

fin.close();

// print

cout << "Gn";
for (int i = 0; i < n; i++){
  for (int j = 0; j < n; j++)
    cout << G[i][j] << " ";
  cout << endl;
}

cout << "G2n";
for (int i = 0; i < n; i++){
    for (int j = 0; j < n; j++)
      cout << G2[i][j] << " ";
    cout << endl;
}

return 0;
}`

Here is the result, all 2 matrices should be positive integer numbers and less than 100

G
0 55 92 92 87 49 51 1 
92 0 62 7 78 32 45 82 
78 51 0 81 91 22 8 73 
54 100 12 0 24 14 33 62 
27 58 54 82 0 50 45 35 
99 63 36 56 91 0 9 34 
22 20 82 66 37 28 0 22 
59 37 95 79 36 7 3 0 

G2
-1 0 0 0 0 0 0 0 
0 0 1239583408 30728 1459795768 0 1239352720 30728 
0 0 0 0 791621423 791621423 791621423 791621423 
0 0 0 0 0 0 0 0 
1633824622 1392535667 1230197573 1298091599 0 0 0 0 
0 0 0 0 0 0 0 0 
0 0 0 0 0 0 0 0 
1599031623 1314210124 1145391171 1397048415 1347376203 1279870559 1982807365 1815048801