Answer to Question #200231 in C++ for zxc

Question

Complete the program by filling in the code (areas in bold). This problem requires 

that you study very carefully the code and the data file already written to prepare you to complete the program.Add another field called letter to the record which is a character that holds the letter grade of the student. This is based on the average of the grades as follows: test1 and test2 are each worth 30% of the grade while final is worth 40% of the grade. The letter grade is based on a 10 point spread. The code will have to be expanded to find the average. 

90-100 A

80-89 B

70-79 C

60-69 D

0-59 F 

Answer 1

graderoll.dat file

Dean DeFino     88  98  99
Sally Johnson   78  89  82
Bill Benny      75  79  81
Thomas Billows  78  84  89 

Grades.cpp 

#include <fstream> //  DIRECTIVE FOR FILES
#include <iostream>
#include <iomanip>
using namespace std;


// This program reads records from a file. The file contains the
// following: student’s name, two test grades and final exam grade.
// It then prints this information to the screen.


const int NAMESIZE = 15;
const int MAXRECORDS = 50;
struct Grades // declares a structure
{
	char name[NAMESIZE + 1];
	int test1;
	int test2;
	int final;
	char letter;
};
typedef Grades gradeType[MAXRECORDS];
void readIt(ifstream& inData, gradeType gradeRec,int& total);
void getGrade(gradeType gradeRec,int total);


int main()
{
	ifstream inData;
	inData.open("graderoll.dat");
	int numRecord; // number of records read in
	gradeType studentRecord;
	if(!inData)
	{
		cout << "Error opening file. n";
		cout << "It may not exist where indicated" << endl;
		return 1;
	}
	readIt(inData,studentRecord,numRecord);
	getGrade(studentRecord,numRecord);
	for (int count = 0; count < numRecord; count++)
	{
		cout << studentRecord[count].name << setw(10)
			<< studentRecord[count].test1
			<< setw(10) << studentRecord[count].test2;
		cout << setw(10) << studentRecord[count].final;
		cout << setw(10) << studentRecord[count].letter << endl;
	}
	cin>>numRecord;
	return 0;
}
//**************************************************************
// readIt
//
// task: This procedure reads records into an array of
// records from an input file and keeps track of the
// total number of records
// data in: data file containing information to be placed in
// the array
// data out: an array of records and the number of records
//
//**************************************************************
void readIt(ifstream& inData, gradeType gradeRec,int& total){
	total = 0;
	inData.get(gradeRec[total].name, NAMESIZE);
	while (inData)
	{
		if(total<MAXRECORDS){
			// READ test1
			inData >> gradeRec[total].test1;
			// READ test2
			inData >> gradeRec[total].test2;
			// READ final
			inData >> gradeRec[total].final;
			total++; // add one to total
			// CONSUME THE END OF LINE
			inData.ignore(NAMESIZE, '\n');
			// READ name
			inData.get(gradeRec[total].name, NAMESIZE);
		}
	}
}


void getGrade(gradeType gradeRec,int total){
	for(int i=0;i<total;i++){
		double averageGrades=gradeRec[i].test1*0.3+gradeRec[i].test2*0.3+gradeRec[i].final*0.4;
		if(averageGrades>=90){
			gradeRec[i].letter= 'A';
		}else if(averageGrades>=80){
			gradeRec[i].letter= 'B';
		}else if(averageGrades>=70){
			gradeRec[i].letter= 'C';
		}else if(averageGrades>=60){
			gradeRec[i].letter= 'D';
		}else{
			gradeRec[i].letter= 'F';
		}
	}
}

Example: