Answer to Question #175136 in C++ for meng

Question

Write a program that lets a lecturer keep track of test scores for their students.

-sample-

How many students are in your class? -5

Invalid number of students, try again.

How many students are in your class? 3

How many test in this class? -10

Invalid number of tests, try again.

How many test in this class?

Ok, lets’ begin  .  .  .

**** Student #1 ****

Enter score for test #1: -50

Invalid score, try again.

Enter score for test #1: 50

Enter score for test #2: 75

Average score for student #1 is 62.50

**** Student #2 ****

Enter score for test #1: 100

Enter score for test #2: 90

Average score for student #2 is 95.00

**** Student #3 ****

Enter score for test #1: -10

Invalid score, try again.

Enter score for test #2: -20

Invalid score, try again.

Enter score for test #2: -30

Invalid score, try again.

Enter score for test #1: 90

Enter score for test #2: 80

Average score for student #3 is 85.00

Average score for all student is 80.83

Answer 1

#include <iostream>
#include <iomanip>
 
using namespace std;
 
int main()
{
	int numberStudents = 0;
	while (true)
	{
		cout << "How many students are in your class? ";
		cin >> numberStudents;
		if (numberStudents <= 0) cout << "Invalid number of students, try again." << endl;
		else break;
	}
	int numberTest = 0;
	cout << endl;
	while(true)
	{
		cout << "How many test in this class? ";
		cin >> numberTest;
		if (numberTest <= 0) cout << "Invalid number of tests, try again." << endl;
		else break;
	}
	cout << endl;
	cout << "Ok, lets begin..." << endl;
	double sum = 0;
	double score = 0;
	double totalSum = 0;
	cout << fixed << setprecision(2);
	for (int i = 1; i <= numberStudents; i++)
	{
		cout << "**** Student #" << i << "****" << endl;
		for (int j = 1; j <= numberTest; j++)
		{
			while(true)
			{
				cout << "Enter score for test #" << j << ": ";
				cin >> score;
				if (score < 0) cout << "Invalid score, try again." << endl;
				else break;
			}
			sum += score;
		}
		totalSum += sum;
		cout << "Average score for student #" << i << " is " << sum / numberTest << endl << endl << endl;
		sum = 0;
	}
	cout << "Average score for all student is " << totalSum / (numberStudents * numberTest) << endl;
	return 0;
}