ifstream different datatypes in other rows

Question

I've just started with C++ a few weeks ago and need some help for my "homework".

I need to read:

row1: int int
row2: int char

from a text file. My code looks like this:

int main() {
  [...]
  ifstream fin(argv[1]);
  int i{0}, tmp;
  while (fin >> tmp) {
    cout << pos << "zahl" << tmp << endl;
    if (pos == 0) {
      wagen = tmp;
    }  // needed for an array
    if (pos == 1) {
      reihen = tmp;
    }
    i++;
    [...] return 0;
  }

my problem is how do you work around row2+? I tried typecasting and googled for over a hour but didn't found anything useful.

Protip: You don't have to read *every* line in the same loop. You can read values outside of any loop as well. — Yksisarvinen, Nov 15 '19 at 19:58
ok, how can i do that ? or do u have any website that explains it ? — maybeAboomerBoi, Nov 15 '19 at 20:14
If you read first row, then the rest of the lines is all the same, right? So, read the first row seprately into some variables and then read the rest of the file in a loop. — Yksisarvinen, Nov 15 '19 at 20:18
ty for your help, but i still dont get it to work, i mave have a to big knowledge gap — maybeAboomerBoi, Nov 15 '19 at 20:47

score 0 · Answer 1 · answered Nov 15 '19 at 20:23

There is nothing preventing you from having such a structure. You simply have to read outside the loop:

int x, y;
std::cin >> x >> y;

int val; 
char c;


while (!std::cin.eof())  /* while the end of the stream has 
                          * not been reached yet */
{
  int val;
  std::cin >> val;

  /* getting characters from a stream is tricky; consider a line such
   * as "123    c\n"; you read the int, 123, but then when you read the
   * character, you'll want the 'c', not a whitespace character, so
   * "std::cin >> std::ws" consumes the "leading" whitespace before the
   * character. */
  char c = (std::cin >> std::ws).get();

  /* next step is to ignore the trailing whitespace on the current line */
  std::cin.ignore(std::numeric_limits<std::streamsize>::max(), '\n');
}

Edit: some explanation is probably needed, so I added it in code comments.

P.S. I haven't tested the code myself.

ty for your help, but i guess im just to dump for that kind of task. — maybeAboomerBoi, Nov 15 '19 at 20:42
@maybeAboomerBoi nobody is. you aren't. Just ask about what you do not understand. If you a beginner in terms of C++, I recommend checking [this](https://stackoverflow.com/q/388242/1673776) out. If you're a beginner in terms of programming, that's fine. You should pick some courses or books if you want to learn! — Victor, Nov 16 '19 at 09:11

ifstream different datatypes in other rows

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