.txt calculation

[puppymew]

I put all the data into a .txt file.
How do I use the information from the .txt file and make some calculation?

inside the .txt file

SQUARE 10.2 12.3
RECTANGLE 5.6 6.7

I have to calculate the area of both shapes.

[coder1]

1) what are the two numbers in front of square?
2) do you want to take two lines of input only or more?

Please explain more

[Daleth]

If the format is always the same:
1) Read in the name of the shape
2) You could store the name for like when you print: "SQUARE has an area of: "
3) Read in the next two numbers and store them in their own variables
4) Now multiply those two variables to get the area.
5) Repeat steps 1-4 (you can use the same variables, because they will be overwritten with/reassigned the new values).

Simple?

[puppymew]

how do I read the numbers from the .txt file? can you be more specific and ? give me some examples? Thanks.

[Daleth]

The standard's file input class is std::ifstream, which is under the <fstream> header. One of the best parts about fstream objects is that you can treat them like cout/cin.

#include <fstream>

int main(){
   std::string filepath("data.txt");//File Name or File Path
   std::ifstream data(filepath); //Opens the file

   if( !data.is_open()) return 2; //Make sure the file was opened successfully

   while(data.good()){//Will stop the loop if there is any problem or if we reach the end of the file
      std::string shape("");
      double side1(0), side2(0);

      data >> shape >> side1 >> side2; //Just like using cin
//...Do stuff with new data...
   }
   data.close(); //Close the file. Not actually necessary, but it is good practice

   return 0;
}

How you read in the data, though, depends on the format the data is written in.