Question

C++
1. Your program should use named string constant for the file name to open the file. Do not add any path to the file name because the path on your computer is not likely to exist on the computer the instructor uses to grade the program. Points may be deducted if you don't follow this instruction.

2. Split statements and comments longer than 80 characters into multiple lines and use proper indentations for the split portions.

(Lab2b.cpp) Write a program to process structured data stored in a file.

The program must be written in accordance to the following plan:

Define Data Structure

Define a data structure named NutritionData that contains these fields

foodName (array of 40 char)

servingSize (double)

calFromCarb (double)

calFromFat (double)

calFromProtein (double)

totalCalories (double)

Use the data types in parentheses for the fields.

Create File

Create a binary file named test.dat. The file name should be defined in a named string constant. The string constant identifier should be used every time the file name is needed in the program.

If the file already exists, print the message, "The file test.dat is an existing file. You can either delete the file or move it to another location and then run the program again." The program should terminate after printing out the message.

Write five records of structured data to the file in binary format. Each record of data contains these fields: food name, serving size in grams, calories from carb, calories from fat and calories from protein.

Use the following data.

Apples raw, 110, 50.6, 1.2, 1.0

Bananas, 225, 186, 6.2, 8.2

Bread pita whole wheat, 64, 134, 14, 22.6

Broccoli raw, 91, 21.9, 2.8, 6.3

Carrots raw, 128, 46.6, 2.6, 3.3

Close the file.

Read Data From File

Open the file and access the third record from the file. The program should use the seek mechanism to access the desired record.

Read the third record.

Process the record by calculating the calories per serving.

Print the third record to the screen.

Close the file.

Test The Program

The output should look exactly as follows:

Food Name: Bread pita whole wheat
Serving Size: 64.0 grams
Calories Per Serving: 170.6
Calories From Carb: 134.0
Calories From Fat: 14.0
Calories From Protein: 22.6

Answer 1

#include<iostream>
#include <fstream>
#include<string>
using namespace std;

//Defining Structure
struct NutritionData{
   string foodName;
   double servingSize,calFromCarb,calFromFat,calFromProtein,totalCalories;  
};

int main () {
// open a file in write mode.
ofstream filestream("test.dat");
if (filestream.is_open())
      {
       // write inputted data into the file.
        filestream << "Apples raw, 110, 50.6, 1.2, 1.0\n";
        filestream << "Bananas, 225, 186, 6.2, 8.2\n";
        filestream << "Bread pita whole wheat, 64, 134, 14, 22.6\n";
        filestream << "Broccoli raw, 91, 21.9, 2.8, 6.3\n";
        filestream << "Carrots raw, 128, 46.6, 2.6, 3.3\n";
        // close the opened file.
        filestream.close();
      }
// Error Case message display
else cout <<"File opening is fail.";

    // open a file in read mode.
   ifstream file("test.dat");
   //initializing string phonenum to store the input_string
   string stringline;
    string nutrionstring;
   //using std::getline to fetch a line from the file and process it:
   int count=0;
   while (std::getline(file, stringline)) {
      // Process strngline here
      count+=1;
      if(count==3){nutrionstring=stringline;}// get the line number 3

   }

   //parsing nutrionstring;
   string s1(nutrionstring);
   string s2(s1, 0, 22);
   string s3 = s1.substr(24,2);
   string s4 = s1.substr(28,3);
   string s5 = s1.substr(33,2);
   string s6 = s1.substr(37,4);
   //type casting values
   double temp =stod (s3);
   double temp1 =stod (s4);
   double temp2 =stod (s5);
   double temp3 =stod (s6);

  

    //assigning values to struct
   struct NutritionData nuc;
    nuc.foodName=s2;
    nuc.servingSize=temp;
    nuc.calFromCarb=temp1;
    nuc.calFromFat=temp2;
    nuc.calFromProtein=temp3;
//    nuc.totalCalories=;
    cout<<nuc.foodName<<endl;
    cout<<"Serving Size:"<<nuc.servingSize<<endl;
    cout<<"Calories From Carb:"<<nuc.calFromCarb<<endl;
    cout<<"Calories From Fat: "<<nuc.calFromFat<<endl;
    cout<<"Calories From Protein:"<<nuc.calFromProtein<<endl;

return 0;
}

Output: