Answer:
void delete_record(student_record *arr, int &size, int age, string name, double gpa) {
int index = -1;
if (arr != NULL && size > 0) {
for (int i = 0; i < size; ++i) {
if (arr[i].age == age && arr[i].name == name && arr[i].gpa == gpa) {
index = i;
break;
}
}
}
if (index != -1) {
for (int i = index; i < size - 1; ++i) {
arr[i] = arr[i + 1];
}
size--;
}
}