Question

You will be given a file that will contain averages for classes which are divided into sections in the following format. The name of this file will be "grades.txt".

A 93
B 82
A 86
C 75 
F 83

You are to write a program that computes the averages for the sections of classes, they are divided into groups that are denoted by a capital letter. You are to use arrays to calculate the average. I recommend using two arrays one to keep a sum of the averages and the other a counter for how many classes have been added to the sum.

The equation for calculating the average is:

(sum of numbers in list) / (number of numbers in list)

Given this you can have one array to keep a sum of the numbers that you are given and the other to keep a count of the number of classes in that section. The section names will be from A - Z and will always be capital letters. The averages will be from 0 - 100 inclusively.

Your program should output to the console the highest average section, lowest average section, and the average score across all of the sections. Output both the section name and the score for that section. To a file you will print the average for each section in alphabetical order. Always output the scores with two decimal places.

To the console:

HIGHEST AVERAGE:................A:98.00
LOWEST AVERAGE:.................H:73.00
AVERAGE SCORE:....................85.00

To a file named "results.txt":

A: 98.00
B: 93.00
C: 85.21
D: 95.12
.
.
.
Z: 78.25

in C++ please

Answer 1

Note: I only take few data in the input file...but this program can work if how many no of records in input file

Could you plz go through this code and let me know if u need any changes in this.Thank You
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// grades.txt

A 93
B 82
A 86
C 75
F 83

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#include <fstream>
#include <iostream>
#include <iomanip>
#include <cstring>
#include <cstdlib>
using namespace std;

// Function Declarations
int findHighestAvg(double grades[], int cnt);
int findLowestAvg(double grades[],int cnt);
double calcGrade(double grade[],int cnt);
int main() {
  
  
   //Declaring variables
   int cnt=0;
ifstream dataIn;
char ch;
   double grade;
  
//Opening the input file
   dataIn.open("grades.txt");
  
   //checking whether the file name is valid or not
if(dataIn.fail())
{
   cout<<"** File Not Found **";
return 1;
}
else
{
//Reading the data from the file
while(dataIn>>ch>>grade)
{
   cnt++;
   }
dataIn.close();
  
// Creating array dynamically
char* groups = new char[cnt];
double* grades=new double[cnt];
  
   dataIn.open("grades.txt");
//Reading the data from the file
for(int i=0;i<cnt;i++)
{
dataIn>>ch>>grade;
groups[i]=ch;
grades[i]=grade;
   }
dataIn.close();
  
//calling the functions
int highIndx=findHighestAvg(grades,cnt);
int lowIndx=findLowestAvg(grades,cnt);
double avg=calcGrade(grades,cnt);
  
//Displaying the output
cout<<"HIGHEST AVERAGE:................"<<groups[highIndx]<<":"<<grades[highIndx]<<endl;

   cout<<"LOWEST AVERAGE:................"<<groups[lowIndx]<<":"<<grades[lowIndx]<<endl;
   cout<<"AVERAGE SCORE:...................."<<avg<<endl;
}
   return 0;
}
int findHighestAvg(double grades[],int cnt)
{
   double max=grades[0];
   int maxIndx=0;
  
   for(int i=0;i<cnt;i++)
   {
       if(max<grades[i])
       {
           max=grades[i];
           maxIndx=i;
       }
      
   }
   return maxIndx;
}
int findLowestAvg(double grades[],int cnt)
{
   double min=grades[0];
   int minIndx=0;
  
   for(int i=0;i<cnt;i++)
   {
       if(min>grades[i])
       {
           min=grades[i];
           minIndx=i;
       }
      
   }
   return minIndx;
}

double calcGrade(double grade[],int cnt)
{
   double sum=0;
   for(int i=0;i<cnt;i++)
   {
       sum+=grade[i];
   }
   return ((double)sum)/cnt;
}

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Output:

_______________Could you plz rate me well.Thank You