Segmentation fault(core dumped) in C++ [closed] - c++

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I'm getting this annoying error when compiling a C++ program. I looked it up and didn't find any answer. It's strange because my code is really basic and shouldn't cause any problems at all but yet it does.. I'm using Ubuntu and CODEBLOCKS IDE for the job. Here's the full code:
#include <iostream>
#include <iomanip>
using namespace std;
struct database
{
string number;
string spec_number;
char group;
float grade;
string name;
string family_name;
};
void FillDatabase(database student[], short N,short &i);
void SplitDatabase(database student[], short N,short i);
int main()
{
short number_of_students,iteration=0;
//ПРОВЕРКА:
cout << "Za kolko studenta shte vyvejdate? ";
cin >> number_of_students;
cin.ignore();
database student[number_of_students];
FillDatabase(student,number_of_students,iteration);
//МЕНЮ ЗА ИЗБОР
SplitDatabase(student, number_of_students,iteration);
return 0;
}
//--------------------------------------------------------------------------------------------------------------------------------------------
void FillDatabase(database student[], short N,short &i)
{
for(i=0;i < N;i++)
{
//ДОПЪЛНИТЕЛНИ ПРОВЕРКИ ЗА ВАЛИДНОСТ:
cout << endl << endl << "VIE VYVEJDATE ZA STUDENT NOMER " << i+1 << "." << endl;
cout << endl << "Vyvedete fakulteten nomer na studenta...";
cin >> student[i].number;
cout << endl << "Vyvedete kod na specialnostta 52(E) ili 61(AIUT)...";
cin >> student[i].spec_number;
cout << endl << "Vyvedete grupa na studenta...";
cin >> student[i].group;
cout << endl << "Vyvedete sreden uspeh ot semestyra...";
cin >> student[i].grade;
cout << endl << "Vyvedete ime na studenta...";
cin >> student[i].name;
cout << endl << "Vyvedete familiya na studenta...";
cin >> student[i].family_name;
cin.ignore();
}
}
void SplitDatabase(database student[], short N,short i)
{
short count_of_E(0);
for(i=0;i < N;i++)if(student[i].spec_number=="52")count_of_E++;
database E_student[count_of_E];
database AIUT_student[N-count_of_E];
for(i=0;i < N;i++)
{
if(student[i].spec_number=="52")
{
E_student[i].number = student[i].number;
E_student[i].spec_number = student[i].spec_number;
E_student[i].group = student[i].group;
E_student[i].grade = student[i].grade;
E_student[i].name = student[i].name;
E_student[i].family_name = student[i].family_name;
}
else
{
AIUT_student[i].number = student[i].number;
AIUT_student[i].spec_number = student[i].spec_number;
AIUT_student[i].group = student[i].group;
AIUT_student[i].grade = student[i].grade;
AIUT_student[i].name = student[i].name;
AIUT_student[i].family_name = student[i].family_name;
}
}
cout << endl << endl << endl << left << "E" << setw(50) << right << "AIUT" << endl << endl;
for(i=0;i < N;i++)
{
cout << left << E_student[i].name << endl;
cout << left << E_student[i].family_name << endl;
cout << left << E_student[i].number << endl;
cout << left << E_student[i].group << endl;
cout << left << E_student[i].grade << endl << endl;
cout << setw(50) << right << AIUT_student[i].name << endl;
cout << setw(50) << right << AIUT_student[i].family_name << endl;
cout << setw(50) << right << AIUT_student[i].number << endl;
cout << setw(50) << right << AIUT_student[i].group << endl;
cout << setw(50) << right << AIUT_student[i].grade << endl;
}
}
/*
string number;
string spec_number;
char group;
float grade;
string name;
string family_name;
61462166 52 2 5.50
*/
I hope that someone lends me a hand here, I'm frustrated....

Answer 1

The problem (when running, not compiling) is in lines like these:
E_student[i].number = student[i].number;
E_student[i].spec_number = student[i].spec_number;
//...
AIUT_student[i].number = student[i].number;
AIUT_student[i].spec_number = student[i].spec_number;
You're looping over student from 0..N-1 -- however E_student and AIUT_student are smaller than N. If N == 4, and E_student and AIUT_student are both of size 2, the last time through the loop you're assigning to AIUT_student[3] or E_student[3] -- past the end of the respective arrays.
You need to keep separate indices for each array:
int ei = 0, ai = 0;
for (i = 0; i < N; i++)
{
if (student[i].spec_number == "52")
{
E_student[ei].number = student[i].number;
E_student[ei].spec_number = student[i].spec_number;
E_student[ei].group = student[i].group;
E_student[ei].grade = student[i].grade;
E_student[ei].name = student[i].name;
E_student[ei].family_name = student[i].family_name;
++ei;
}
else
{
AIUT_student[ai].number = student[i].number;
AIUT_student[ai].spec_number = student[i].spec_number;
AIUT_student[ai].group = student[i].group;
AIUT_student[ai].grade = student[i].grade;
AIUT_student[ai].name = student[i].name;
AIUT_student[ai].family_name = student[i].family_name;
++ai;
}
}

Answer 2

your problem is that you adress the both partial arrays AIUT_student and E_student with the index of the whole student array. this will result in an access violation latest at N/2+1