Write a program that reads test scores up to 30 into an array. sentinel will stop when -1 is entered.

Question

Write functions that:
1. read the scores into arrays
2. computes the distribution based on whether they are As, Bs and so on
3. find how many students have the same score
4. display the number of studdents, the distribution, number of students with the same score.

This is what I have so far. I have part 1. Now I need help in total the number of students which is based on the number of grades entered. Then I need help with 3. and 4.

#include <iostream>
#include <iomanip>
#include <string>
#include <cmath>

using namespace std;

void readinfo(int);
int totalstudents (int);
void displayinfo;

int main()
{
const int VALS_LEN = 30;

int totalstudents[VALS_LEN];

cout << "Welcome to the student test manager!" << endl;
readinfo(VALS_LEN);
cout << endl;
cout << "Report " << endl;
cout << "______ " << endl;
cout << endl;
cout << "Number of students: " << totalstudents << endl;

system ("pause");
return 0;
}

void readinfo(int testscores)
{
for( int studentScores = 0; studentScores < testscores; studentScores ++)
{
while(testscores != -1)
{
cout << "Please enter student test scores (or -1 to quit): ";
cin >> testscores;

}
}
}

int totalstudents (int students)
{
int testscores;
int total = 0;

for (int students = 0; students < 30; students ++)
{
total = testscores ++;
return total;

}
}

void displayinfo