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#include <iostream>
#include <fstream>
#include <cstring>
using namespace std;
struct Student
{
char name[30];
int age;
int fn;
};
void initStudent(Student& st, const char* name, int age, int fn)
{
strcpy(st.name, name);
st.age = age;
st.fn = fn;
}
void saveToFile(const Student* students, size_t count, ofstream& file)
{
file.write((const char*)students, count * sizeof(Student));
}
size_t getFileSize(ifstream& f)
{
size_t currentPos = f.tellg();
f.seekg(0, ios::end);
size_t size = f.tellg();
f.seekg(currentPos);
return size;
}
void readFromFile(Student*& ptr, size_t& studentsCount, ifstream& f)
{
size_t sizeOfFile = getFileSize(f);
studentsCount = sizeOfFile / sizeof(Student);
ptr = new Student[studentsCount];
f.read((char*)ptr, sizeOfFile);
}
int main()
{
Student* arr;
size_t count;
ifstream file("students.dat");
readFromFile(arr, count, file);
for (int i = 0; i < count; i++)
std::cout << "Name: " << arr[i].name << ", age: " << arr[i].age << ", fn: " << arr[i].fn << std::endl;
delete[] arr;
}
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