C++ Printing the member who got the highest in a result - c++

Question

This is a problem given to me by my computer mentor and I am trying to explain the problem in simple words(I must remind you that my mentor has only taught me loops array structure. I cannot use class for this problem)
Take two matrix
Print the name of n students in one matrix
Print the id, marks in 5 subject of the students in another 2d
matrix (n*6)
Find the student who got the highest in the total of 5 subject and
print the student name with marks of each subject and his total
marks.(i think we have to us a structure)
For example: The highest marks is secured by :
Name;
id no;
marks in sub 1;
marks in sub 2;
marks in sub 3;
marks in sub 4;
marks in sub 5;
total;
Then print the id and the name of the student who got highest in
each subject
For example:
Subject 1 ID name
Subject 2 ID name .....
I have being able to solve it fully till point (3). but unable to print the person who got the highest in each subject ; and I am facing problem to print the person who got highest in each subject as I have to use many variables(I'm not using structure)
What I have tried so far:
#include <iostream>
using namespace std;
int main()
{
//making 1st array to print the names of the students
char x[500][1000];
int num, i;
cout << "Enter the number of student's data you want to input" << endl;
cin >> num;
cout << endl;
cout << "NAME LIST" << endl;
cout << endl;
for(i = 0; i < num + 1; i++)
{
cin.getline(x[i], 1000);
}
//making a 2nd array to print the id, marks in 5 subjects of the students
int y[num][6];
int a, b;
cout << endl;
cout << endl;
cout << "DETAILS OF THE STUDENT" << endl;
cout << endl;
for(int a = 0; a < num; a++)
{
cout << "ID no of student " << a + 1 << ":";
cin >> y[a][0];
cout << "Marks in subject 1:";
cin >> y[a][1];
cout << "Marks in subject 2:";
cin >> y[a][2];
cout << "Marks in subject 3:";
cin >> y[a][3];
cout << "Marks in subject 4:";
cin >> y[a][4];
cout << "Marks in subject 5:";
cin >> y[a][5];
cout << endl;
}
cout << endl;
cout << "The data you inputed:";
cout << endl;
for(a = 0; a < num; a++)
{
for(b = 0; b < 6; b++)
{
cout << y[a][b] << " ";
}
cout << endl;
}
cout << endl;
cout << endl;
//finding the member who got the highest marks
int s = 0;
int largestSum = 0;
for(a = 0; a < num; i++)
{
for(b = 0; b<6; b++)
{
s += y[a][b];
}
// check to see if we have computed a new larger sum and save it if we have.
if(s > largestSum)
{
largestSum = s;
}
}
cout << "largest sum: " << largestSum << endl;
return 0;
}

Answer 1

int s = 0; <- s needs to be reset to zero in each loop
int largestSum = 0;
for(a = 0; a<num; i++) <- loop doesn't break
{
for(b = 0; b<6; b++) <- b should start at 1
{
s += y[a][b];
}
if(s > largestSum)
{
largestSum = s;
}
}
i is incremented while a remains constant and the loop goes forever.
s is not reset to zero, so you sum all the values.
The first index at b = 0 is supposed to be student id, it should be skipped. Try instead:
int largestSum = 0;
for(a = 0; a < num; a++)
{
int s = 0;
for(b = 1; b < 6; b++)
s += y[a][b];
if(s > largestSum)
largestSum = s;
}

Answer 2

Here's something to go off of.
Note that I only made one matrix and put the Student objects in it.
#include <ctime>
#include <iostream>
#include <string>
#include <vector>
const std::vector<std::vector<std::string>> names = {
{"Ralph", "Gerald", "Henry", "Jessica", "Bob"},
{"Tara", "Tami", "Mike", "Loretta", "Jean"},
{"Jesse", "John", "Carl", "Josh", "Abby"},
{"Carson", "Don", "George", "Hillary", "David"},
{"Micah", "Charlie", "Maximus", "Leonidas", "Xerxes"}
};
int main()
{
time_t seconds;
time(&seconds);
srand((unsigned int)seconds);
struct Subjects
{
unsigned int subject[5] = {};
};
struct Student
{
Subjects sub;
std::string name;
int id;
Student() : name("nobody"), id(-1) {};
Student(const std::string& name, const unsigned int& id) : name(name), id(id) {}
};
Student stud_matrix[5][5] = {};
int count = 0;
for (size_t i = 0; i != 5; ++i)
{
for (size_t j = 0; j != 5; ++j)
{
stud_matrix[i][j].name = names[i][j];
stud_matrix[i][j].id = count;
++count;
}
}
std::cout << "All student names:\n";
for (size_t i = 0; i != 5; ++i)
{
for (size_t j = 0; j != 5; ++j)
{
std::cout << stud_matrix[i][j].name << ' ';
}
std::cout << std::endl;
}
std::cout << std::endl;
std::cout << "All student IDs:\n";
for (size_t i = 0; i != 5; ++i)
{
for (size_t j = 0; j != 5; ++j)
{
std::cout << stud_matrix[i][j].id << ' ';
}
std::cout << std::endl;
}
std::cout << std::endl;
for (size_t i = 0; i != 5; ++i)
{
for (size_t j = 0; j != 5; ++j)
{
stud_matrix[i][j].sub.subject[0] = (rand() % 100 + 1);
stud_matrix[i][j].sub.subject[1] = (rand() % 100 + 1);
stud_matrix[i][j].sub.subject[2] = (rand() % 100 + 1);
stud_matrix[i][j].sub.subject[3] = (rand() % 100 + 1);
stud_matrix[i][j].sub.subject[4] = (rand() % 100 + 1);
}
}
Student best_student;
unsigned int highest_grade = {};
for (size_t i = 0; i != 5; ++i)
{
for (size_t j = 0; j != 5; ++j)
{
if (stud_matrix[i][j].sub.subject[0] > highest_grade)
{
highest_grade = stud_matrix[i][j].sub.subject[0];
best_student = stud_matrix[i][j];
}
if (stud_matrix[i][j].sub.subject[1] > highest_grade)
{
highest_grade = stud_matrix[i][j].sub.subject[1];
best_student = stud_matrix[i][j];
}
if (stud_matrix[i][j].sub.subject[2] > highest_grade)
{
highest_grade = stud_matrix[i][j].sub.subject[2];
best_student = stud_matrix[i][j];
}
if (stud_matrix[i][j].sub.subject[3] > highest_grade)
{
highest_grade = stud_matrix[i][j].sub.subject[3];
best_student = stud_matrix[i][j];
}
if (stud_matrix[i][j].sub.subject[4] > highest_grade)
{
highest_grade = stud_matrix[i][j].sub.subject[4];
best_student = stud_matrix[i][j];
}
}
}
std::cout << "The highest scoring student in any one subject is: " << best_student.name << std::endl;
std::cout << "ID: " << best_student.id << std::endl;
std::cout << "Marks in sub1: " << best_student.sub.subject[0] << std::endl;
std::cout << "Marks in sub2: " << best_student.sub.subject[1] << std::endl;
std::cout << "Marks in sub3: " << best_student.sub.subject[2] << std::endl;
std::cout << "Marks in sub4: " << best_student.sub.subject[3] << std::endl;
std::cout << "Marks in sub5: " << best_student.sub.subject[4] << std::endl;
std::cout << "Total: " << best_student.sub.subject[0] + best_student.sub.subject[1] + best_student.sub.subject[2] +
best_student.sub.subject[3] + best_student.sub.subject[4] << std::endl;
std::cout << std::endl;
Student stud_sub1;
Student stud_sub2;
Student stud_sub3;
Student stud_sub4;
Student stud_sub5;
unsigned int high_sub1 = {};
unsigned int high_sub2 = {};
unsigned int high_sub3 = {};
unsigned int high_sub4 = {};
unsigned int high_sub5 = {};
for (size_t i = 0; i != 5; ++i)
{
for (size_t j = 0; j != 5; ++j)
{
if (stud_matrix[i][j].sub.subject[0] > high_sub1)
{
high_sub1 = stud_matrix[i][j].sub.subject[0];
stud_sub1 = stud_matrix[i][j];
}
if (stud_matrix[i][j].sub.subject[1] > high_sub2)
{
high_sub2 = stud_matrix[i][j].sub.subject[1];
stud_sub2 = stud_matrix[i][j];
}
if (stud_matrix[i][j].sub.subject[2] > high_sub3)
{
high_sub3 = stud_matrix[i][j].sub.subject[2];
stud_sub3 = stud_matrix[i][j];
}
if (stud_matrix[i][j].sub.subject[3] > high_sub4)
{
high_sub4 = stud_matrix[i][j].sub.subject[3];
stud_sub4 = stud_matrix[i][j];
}
if (stud_matrix[i][j].sub.subject[4] > high_sub5)
{
high_sub5 = stud_matrix[i][j].sub.subject[4];
stud_sub5 = stud_matrix[i][j];
}
}
}
std::cout << "Best of subject:\n";
std::cout << "Subject 1:\nID: " << stud_sub1.id << ' ' << stud_sub1.name << " Score: " << high_sub1 << std::endl;
std::cout << "Subject 2:\nID: " << stud_sub2.id << ' ' << stud_sub2.name << " Score: " << high_sub2 << std::endl;
std::cout << "Subject 3:\nID: " << stud_sub3.id << ' ' << stud_sub3.name << " Score: " << high_sub3 << std::endl;
std::cout << "Subject 4:\nID: " << stud_sub4.id << ' ' << stud_sub4.name << " Score: " << high_sub4 << std::endl;
std::cout << "Subject 5:\nID: " << stud_sub5.id << ' ' << stud_sub5.name << " Score: " << high_sub5 << std::endl;
system("pause");
return 0;
}
Sample Output:
All student names:
Ralph Gerald Henry Jessica Bob
Tara Tami Mike Loretta Jean
Jesse John Carl Josh Abby
Carson Don George Hillary David
Micah Charlie Maximus Leonidas Xerxes
All student IDs:
0 1 2 3 4
5 6 7 8 9
10 11 12 13 14
15 16 17 18 19
20 21 22 23 24
The highest scoring student in any one subject is: Bob
ID: 4
Marks in sub1: 77
Marks in sub2: 67
Marks in sub3: 7
Marks in sub4: 99
Marks in sub5: 66
Total: 316
Best of subject:
Subject 1:
ID: 23 Leonidas Score: 95
Subject 2:
ID: 18 Hillary Score: 92
Subject 3:
ID: 19 David Score: 98
Subject 4:
ID: 4 Bob Score: 99
Subject 5:
ID: 22 Maximus Score: 98