Printing value in void to other void - c++

Question

I'm trying to print a value found in the "getvalue" void in the "show" void. I get an error:
error: 'Students' was not declared in this scope
#include <iostream>
using namespace std;
int studentNumber=0;
int testNumber=0;
struct Student
{
string name,grade;
int studentNo,*testResults;
double average;
};
void getValue()
{
cout << "Enter the number of students: ";
cin >> studentNumber;
cout << "Enter the number of tests: ";
cin >> testNumber;
Student* Students = new Student[studentNumber];
for(int i=0; i< studentNumber; i++)
{
cout<< "\n" << "Enter the name of the " << i+1 << ". student: ";
cin >> Students[i].name;
cout<< "\n" << "Enter the number of the " << i+1 << ". student: ";
cin >> Students[i].studentNo;
Students[i].testResults = new int[testNumber];
for(int z=0; z<testNumber; z++)
{
cout<< "\n" << "Enter the " << z+1 << ". exam grade of the " << i+1 << ". student: " ;
cin >> Students[i].testResults[z];
}
}
}
void show()
{
for(int i=0; i < studentNumber; i++)
{
cout<< "\n" << Students[i].name;
cout<< "\n" << Students[i].studentNo;
for(int z=0; z<testNumber; z++)
{
cout<< "\n" <<Students[i].testResults[z];
}
}
}
int main()
{
getValue();
show();
}
I'm trying to show the obtained values ​​in another void called "show" but failed. (The general structure of the code that must be in a different void must be another void named "show" in my homework)

Answer 1

You have to pass the value.
It can be done via reference:
// omit
void getValue(Student*& Students) // add reference argument
{
cout << "Enter the number of students: ";
cin >> studentNumber;
cout << "Enter the number of tests: ";
cin >> testNumber;
// don't declare here and use the arugment
Students = new Student[studentNumber];
// omit
}
void show(Student* Students) // add argument (need not be reference)
{
// omit
}
int main()
{
// add variable for arguments and use that
Student* s;
getValue(s);
show(s);
}
Or via global variable:
// omit
// declare variable here (as global)
static Student* Students;
void getValue()
{
cout << "Enter the number of students: ";
cin >> studentNumber;
cout << "Enter the number of tests: ";
cin >> testNumber;
// don't declare here and use the global variable
Students = new Student[studentNumber];
// omit
}
void show()
{
// omit
}
int main()
{
getValue();
show();
}

Answer 2

Instead of raw arrays, it might be good to use std::vector<Student>. It'd be easy to replace:
Student* Students = new Student[studentNumber];
with:
#include <vector>
...
std::vector<Student> Students(studentNumber);
(pretty much everything else should be the same) and then for the actual error you're seeing, since the Students array only exists inside the scope of the getValue() function, you'll need to return it so that show() can the array too. Consider changing the code to something like (assuming you're using the vector):
std::vector<Student> getValue() {
...
return Students;
}
void show(std::vector<Student> Students)
...
}
int main() {
auto Students = getValue();
show(Students);
}