Question

Language is C++

NOTE:

No arrays should be used to solve problems and No non-constants global variables should be used.

PART B: (Statistics Program) – (50%)

Please read this lab exercise thoroughly, before attempting to write the program.

Write a program that reads the pairs of group number and student count from the text file (user must enter name of file) and:

1. Displays the number of groups in the file (5 %)
2. Displays the number of even and odd student count (5%)
3. Displays the sum of the even student count and the sum of the odd student count as well as the sum of all the student count (5%)
4. Displays the group numbers of the largest student count and the smallest student count (5 %)
5. Computes the average of the largest and smallest student count (10 %)
6. Compute the sum of ALL the digits in the largest student count (i.e. 952 – Sum is 9+5+2 = 16) (15 %)

Assume the contents of the file are as follows but that the pairs of data can change later:

1 25

2 123

3 475

4 61

5 77

6 910

7 234

8 138

9 134

10 95

11 674

12 345

13 31

14 211

15 952

16 873

17 22

18 7

19 876

20 347

21 450

The following is a sample output: User input in red

What is name of the input file? integers.dat

The number of groups in the file is 21

There are 12 odd student count and 9 even student count

The sum of the odd student count is 2645

The sum of the even student count is 4390

The sum of all the student count is 7035

The group number of the largest student count is 15

The group number of the smallest student count is 18

The average of 952 and 7 is 479.5

The sum of all the digits in the largest student count is 16

NOTE:

1. Use two decimal point precision for the average

2. To check your code, adjust one of the student count in the file, recompile your code and run again (suggest changing the largest or smallest student count )

3. Even though there are 21 pairs of numbers in the file, the program should NOT presume there will always be 21 pairs of numbers. In other words, you should not solve this problem by declaring 21 pairs of values. If I choose to use another integers.dat file other than the one provided with the assignment, your program should still work correctly with that file as well. All you can assume is that a series of integers will be read in from the file. Therefore, you need to implement a solution that uses the repetition control structures (for, while, do…while) in the reading and processing of these values to produce your output.

Answer 1

Rate my solution and please do comment if any doubt

Code:

#include<iostream>
#include<fstream>
#include<string>
#include<cstdlib>
using namespace std;
int main(){
   ifstream file;
   //this is the file pointer variable
   string line;
   string filename;
   int x,y,count=0,odd_count=0,even_count=0;
   int max,min,even_sum=0,odd_sum=0;
   int max_grp,min_grp;
   //above declarations are the variable for all the given requirements
   cout<<"What is name of the input file? ";
   cin>>filename;
   //filename is variable for file name
   file.open(filename.c_str());
   //c_str() will return a null terminated string
   getline(file,line);
   //getline is used for reading each line
   while(file){
       x=line.find(' ');
       //It will find the space between the pair
       //After the space is our required second number
       //Space is found to convert second number(string) to int
       //below if is used to skip new line
       if(x==-1){
           getline(file,line);
           //read each line
           continue;
       }
       //atoi() will convert stringt to int
       //substr() will find the substring (second number)
       //c_str() will return a null terminated string
       y=atoi(line.substr(x+1).c_str());  
       if(count==0){
           //initially max,min are the first group student count
           //If new maximum,minimum is found later it will be updated
           max=y;
           max_grp=count+1;
           min_grp=count+1;
           min=y;
       }
       else{
           if(max < y){
               //new maximum is found and updated
               max=y;
               max_grp=count+1;
           }
           if(min > y){
               //new minimum is found and updated
               min =y ;
               min_grp=count+1;
           }
       }
       if(y%2==0){
           //Even count and even sum is calculated here
           even_count++;
           even_sum+=y;
       }
       else{
           //Odd count and odd sum is calculated here
           odd_count++;
           odd_sum+=y;
       }
       //new line is read
       getline(file,line);  
       //count is incremented to find number of groups
       count++;
   }
  
   int n,sum=0;
   n=max;
   //below loop is used to find The sum of all the digits in the largest student
   while(n>0){
       //loop will end when there are no digits to add
       sum += (n%10);
       //last digit is taken and added to the sum
       n /= 10;
       //last digit is removed
   }
   cout<<"The number of groups in the file is "<<count<<endl;
   cout<<"There are "<<odd_count<<" odd student count and "<<even_count<<" even student count"<<endl;
   cout<<"The sum of the odd student count is "<<odd_sum<<endl;
   cout<<"The sum of the even student count is "<<even_sum<<endl;
   cout<<"The sum of all the student count is "<<odd_sum+even_sum<<endl;
   cout<<"The group number of the largest student count is "<<max_grp<<endl;
   cout<<"The group number of the smallest student count is "<<min_grp<<endl;
   printf("The average of %d and %d is %.2f\n",max,min,(float)(max+min)/2.0);
   cout<<"The sum of all the digits in the largest student count is "<<sum<<endl;
   return 0;
}

Output:

The below is for the input data given in the question . You can try for your own input

Note: The value given for sum of the odd student count is wrong

Below is the correct answer.Please check with your calculator