Need a little bit of help :)

[YesU]

Hello, guys :)

I get that kind of question: Read from file all the numbers below, first row shows how much formulas you have ( must be show in program), after that the numbers a b c must be take in sum. So I have to get 10 answers of those formulas.
10
1 2 3
4 5 6
7 8 9
10 11 12
13 14 15
16 17 18
19 20 21
22 23 24
25 26 27
28 29 30

Thank you, Regards :)

[Chervil]

There's a tutorial on files here (which probably tells you more than you need at this stage)
http://www.cplusplus.com/doc/tutorial/files/
... but still worth going through. The section on Text files is most applicable here.

For your question, the main thing to bear in mind is that reading from a file in C++ can be almost the same as getting input from cin.

First open the file, then read the first integer.
Then repeat that many times (use a for loop), read three integers and do the required processing.
You should add error checking, particularly to confirm that the file is opened properly