The document describes three programming tasks in C++ focused on data processing for student grades. The first program calculates averages, minimums, and maximums of assignment grades using call by reference, the second does the same using call by value, and the third involves several functions for handling arrays, including reading from a file and performing various calculations like finding means and determining the existence of user-input keys. Each program emphasizes utilizing different function calling mechanisms and modular programming practices.

1. Program 1: (Practicing an example of function using call by reference)
Write a program that reads a set of information related to students in C++ class and prints them
in a table format. The information is stored in a file called data.txt. Each row of the file contains
student number, grade for assignment 1, grade for assignment 2, grade for assignment 3, and
grade for assignment 4. Your main program should read each row, pass the grades for the three
assignments to a function called ProcessRow to calculate the average of the grades, minimum of
the four assignments, and the maximum of the four assignments. The results (average,
maximum, and minimum) should be returned to the main program and the main program prints
them on the screen in a table format. For example, if the file includes
126534 7 8 10 7
321345 5 6 4 9
324341 8 3 8 5
your program should print
Std-Id A1 A2 A3 A4 Min Max Average
----------------------------------------------------------------------------------
126534 7 8 10 7 7 10 8
321345 5 6 4 9 4 9 6
324341 8 3 8 5 3 8 6
You must use call by reference to do the above question.
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Program 2: (Practicing an example of function using call by value)
Repeat the above question using call by value. This means you need to have three different
functions: one to calculate the average, another to calculate the minimum, and the third one to
calculate the maximum. This is how to call these functions:
Max = CalculateMax(A1,A2,A3, A4);
Min = CalculateMin(A1,A2,A3, A4);
Average = CalculateAvg(A1,A2,A3, A4);
_________________________________________________________________
Program 3:
Write a program with several functions that performs the following tasks. :
Create a function that reads the following 5 float numbers from the file data.txt into array Called
Arr1.
12.0 15.0 29.3 25.0 93.2

2. Copy array Arr1 into array Arr2 in reverse order
Print array Arr1.
Print array Arr2.
Find the number of elements in array Arr1 that are >= 80 and <=100.
Find the number of the elements in array Arr1 in which their contents are divisible by 5
Find the index of the elements in array Arr1 in which their contents are divisible by 3.
Find mean (average) in array Arr1.
Find the maximum number in array Arr1.
Ask the user to input a key. Then search for the key in array Arr1 and inform the user about the
existence (true / false) of the key in array
Your program should include several functions.
A function for filling up the information from file into an array (part a should call this function)
A function that does the copying of one array into another in reverse order. Arrays must have the
same size (part b should call this function)
Printing any array with any size (part c and d should call this function)
finding and returning the number of elements between 80 and 100 in any array with any size
(part e calls this function)
finding and returning the number of elements in an array that are divisible by 5 (part f calls this
function)
printing the index of elements in an array that are divisible by 3 (part g calls this function)
finding and returning the mean (average) of elements in any array with any size (part h calls this
function)
finding and returning the minimum number in any array of any size (part i calls this function)
searching for a key in any array of any size and returning true/false as result (part j calls this
function)
Note: If your function is supposed to return a value, then do not print anything inside the
function. It would be the job of the main program to print the result on the screen. However, if
the function is supposed to print information (like the print function), then you can use cout
statement inside the function to print the related information.
Also, any parameter that is not supposed to be changed inside a function must be declared as
constant parameter.
// I only need part 3

3. Solution
#include "stdafx.h"
#include
#include
#include
#include
#include
using namespace std;
struct StudentData
{
int studentID;
string first_name;
string last_name;
int exam1;
int exam2;
int exam3;
int total;
char ch;
};
const int SIZE = 9;
const int INFO = 4;
void openInputFile(ifstream &, string);
void getTotal(StudentData[]);
void getGrade(StudentData[]);
void calcLowest(StudentData[], int &, int &, int &, int &, int[]);
void calcHighest(StudentData[], int &, int &, int &, int &, int[]);
void getAverage(StudentData[], int, double &, double &, double &, double &, double[]);
void getStd(StudentData[], double &, double &, double &, double &, double &, double &,
double &, double &, double[]);
void print(StudentData[], int[], int[], double[], double[]);
void sort(StudentData[]);
int main()
{
StudentData arr[SIZE];

4. int lowest1, lowest2, lowest3, lowest4;
int highest1, highest2, highest3, highest4;
double average1 = 0, average2 = 0, average3 = 0, average4 = 0;
double std1 = 0, std2 = 0, std3 = 0, std4 = 0;
int lowest[INFO] = {};
int highest[INFO] = {};
double average[INFO] = {};
double standardDeviation[INFO] = {};
ifstream inFile;
string inFileName = "C:UsersLisaDesktopscores.txt";
openInputFile(inFile, inFileName);
for(int count = 0; count < SIZE; count++)
{
inFile >> arr[count].studentID >> arr[count].first_name >> arr[count].last_name >>
arr[count].exam1 >> arr[count].exam2 >> arr[count].exam3;
}
inFile.close();
getTotal(arr);
getGrade(arr);
calcLowest(arr, lowest1, lowest2, lowest3, lowest4, lowest);
calcHighest(arr, highest1, highest2, highest3, highest4, highest);
getAverage(arr, SIZE, average1, average2, average3, average4, average);
getStd(arr, std1, std2, std3, std4, average1, average2, average3, average4, standardDeviation);
cout << " ";
print(arr, lowest, highest, average, standardDeviation);
cout << " ";
sort(arr);
print(arr, lowest, highest, average, standardDeviation);
system("PAUSE");
return 0;
}
void openInputFile(ifstream &inFile, string inFileName)
{
inFile.open(inFileName);
if (!inFile)
{

5. cout << "Error to open file." << endl;
cout << endl;
return;
}
}
void getTotal(StudentData arr[])
{
for(int i = 0; i < SIZE; i++)
{
arr[i].total = arr[i].exam1 + arr[i].exam2 + arr[i].exam3;
}
}
void getGrade(StudentData arr[])
{
for(int i = 0; i < SIZE; i++)
{
if(arr[i].total >= 270)
arr[i].ch = 'A';
else if(arr[i].total >= 240)
arr[i].ch = 'B';
else if(arr[i].total >= 210)
arr[i].ch = 'C';
else if(arr[i].total >= 180)
arr[i].ch = 'D';
else
arr[i].ch = 'F';
}
}
void calcLowest(StudentData arr[], int &lowest1, int &lowest2, int &lowest3, int &lowest4, int
lowest[])
{
int smallest = 0;
lowest1 = arr[0].exam1;
lowest2 = arr[0].exam2;
lowest3 = arr[0].exam3;
lowest4 = arr[0].total;

6. for (int i = 0; i < SIZE; i++)
{
if (lowest1 > arr[i].exam1)
{
lowest1 = arr[i].exam1;
smallest = i;
}
if (lowest2 > arr[i].exam2)
{
lowest2 = arr[i].exam2;
smallest = i;
}
if (lowest3 > arr[i].exam3)
{
lowest3 = arr[i].exam3;
smallest = i;
}
if (lowest4 > arr[i].total)
{
lowest4 = arr[i].total;
smallest = i;
}
}
for(int index = 0; index < INFO; index++)
{
if(index == 0)
lowest[0] = lowest1;
else if(index == 1)
lowest[1] = lowest2;
else if(index == 2)
lowest[2] = lowest3;
else if(index == 3)
lowest[3] = lowest4;
else
cout << "Fail!" << endl;
}

7. }
void calcHighest(StudentData arr[], int &highest1, int &highest2, int &highest3, int &highest4,
int highest[])
{
int biggest = 0;
highest1 = arr[0].exam1;
highest2 = arr[0].exam2;
highest3 = arr[0].exam3;
highest4 = arr[0].total;
for (int i = 0; i < SIZE; i++)
{
if (highest1 < arr[i].exam1)
{
highest1 = arr[i].exam1;
biggest = i;
}
if (highest2 < arr[i].exam2)
{
highest2 = arr[i].exam2;
biggest = i;
}
if (highest3 < arr[i].exam3)
{
highest3 = arr[i].exam3;
biggest = i;
}
if (highest4 < arr[i].total)
{
highest4 = arr[i].total;
biggest = i;
}
}
for(int index = 0; index < INFO; index++)
{
if(index == 0)
highest[0] = highest1;

8. else if(index == 1)
highest[1] = highest2;
else if(index == 2)
highest[2] = highest3;
else if(index == 3)
highest[3] = highest4;
else
cout << "Fail!" << endl;
}
}
void getAverage(StudentData arr[], int size, double &average1, double &average2, double
&average3, double &average4, double average[])
{
int sum1 = 0, sum2 = 0, sum3 = 0, sum4 = 0;
for(int i = 0; i < SIZE; i++)
{
sum1 += arr[i].exam1;
sum2 += arr[i].exam2;
sum3 += arr[i].exam3;
sum4 += arr[i].total;
}
average1 += static_cast(sum1)/size;
average2 += static_cast(sum2)/size;
average3 += static_cast(sum3)/size;
average4 += static_cast(sum4)/size;
for(int index = 0; index < INFO; index++)
{
if(index == 0)
average[0] = average1;
else if(index == 1)
average[1] = average2;
else if(index == 2)
average[2] = average3;
else if(index == 3)
average[3] = average4;
else

9. cout << "Fail!" << endl;
}
}
void getStd(StudentData arr[], double &std1, double &std2, double &std3, double &std4, double
&average1, double &average2, double &average3, double &average4, double
standardDeviation[])
{
double deviationSum1 = 0, deviationSum2 = 0, deviationSum3 = 0, deviationSum4 = 0;
for(int i = 0; i < SIZE; i++)
{
deviationSum1 += pow((arr[i].exam1 - average1), 2);
deviationSum2 += pow((arr[i].exam2 - average2), 2);
deviationSum3 += pow((arr[i].exam3 - average3), 2);
deviationSum4 += pow((arr[i].total - average4), 2);
}
std1 = sqrt(deviationSum1 / ((SIZE) - 1));
std2 = sqrt(deviationSum2 / ((SIZE) - 1));
std3 = sqrt(deviationSum3 / ((SIZE) - 1));
std4 = sqrt(deviationSum4 / ((SIZE) - 1));
for(int index = 0; index < INFO; index++)
{
if(index == 0)
standardDeviation[0] = std1;
else if(index == 1)
standardDeviation[1] = std2;
else if(index == 2)
standardDeviation[2] = std3;
else if(index == 3)
standardDeviation[3] = std4;
else
cout << "Fail!" << endl;
}
}
cout << " ";
}
void sort(StudentData arr[])

10. {
StudentData temp;
for (int i = 0; i < (SIZE - 1); i++)
{
for (int j = i + 1; j < SIZE; j++)
{
if (arr[i].last_name > arr[j].last_name)
{
temp = arr[i];
arr[i] = arr[j];
arr[j] = temp;
}
}
}
}