Question

Write a program in C++ to: 1. Read all records from a binary file (also attached to this email) to arrays; (the record structure: student number (20 bytes), grade (integer)) 2. Sort the list according to test scores; 3. Calculate the average test score for the class and print on the screen; 4. write sorted records to a new binary file. For example:

The records in the original file:

1 89

2 95

3 76

The new file sorted by scores:

3 76

1 89

2 95

Answer 1

Please find below the required code for above problem statement

#include<iostream>
#include<string>
#include<fstream>
#include<sstream>
using namespace std;
//declare the struct of record
struct record{
   int stu_no;
   int stu_grade;
};

int main()
{
   //declared array of struct
   record array[100];
   //declared input and outputfile
   char input[30]="input.txt";
   char output[30]="output.txt";
   int count=0;
   string line;
   ifstream fin;
   ofstream fout;
   //calculating the grade while reading the data
   float gradesum=0;
   //opening the file for reading
   fin.open(input,ifstream::in);
   while(getline(fin,line))
   {
   //   cout<<line<<endl;
       int i=0;
       string s;
       int id,grade;
       stringstream ss(line);
       //using space delimeter breaking the id and grade
       while(getline(ss,s,' '))
       {
           if(i==0)
           {
               id=stoi(s);
              
           }
           else{
               grade=stoi(s);
               gradesum=gradesum+stof(s);
           }
           i++;
       }
   //storing the grade into record strucutre
       record r;
           r.stu_no=id;
           r.stu_grade=grade;
  
           array[count]=r;
           count++;
   }
//sorting the data based on grade
   for(int k=0;k<count-1;k++)
   {
      
       for(int l=k+1;l<count;l++)
       {
      
           if(array[l].stu_grade<array[k].stu_grade)
           {
          
               record temp=array[k];
               array[k]=array[l];
               array[l]=temp;
           }
       }
   }
   //printing average grade on console
   cout<<"Average of grade : "<<gradesum/count<<endl;
   fout.open(output);
   //writting the sorted to file
   for(int k=0;k<count;k++)
   {
      
       fout<<array[k].stu_no<<" "<<array[k].stu_grade<<endl;
   }
   return 0;
}//end of code

CONSOLE OUTPUT

CARakeshlttlc_cppCodelscore.exe verage of grade: 86.6667 Process exited after 0.4214 seconds with return value 0 Press any key to continue . . .

output.txt

output.txt Notepad File Edit Format View Help 76 1 89 2 95

please do let me know if u have doubts related to solution