факин булщит

#include <stdlib.h>
#include <iostream>
#include <cstdlib>
#include <ctime>

using namespace std;

int main_menu ();
void learn_menu();
void test_menu();
void fragment_test(int number);
void full_test();
void print_ftable(int number);
void print_table();
#define TESTS_COUNT 5

int main_menu ()
{
	system("cls");
	int menu_choice = 0;
	std::cout<< "1 : learn\n"<<"2 : test"<<endl;
	std::cin>>menu_choice;
	if (menu_choice == 1)
	learn_menu();
	else if (menu_choice == 2)
	test_menu();
	else if (menu_choice==0) return 0;
	else main_menu();
}

//вывести кусок таблицы для заданного числа
void print_ftable(int number)
{
	cout<<endl;
	for(int i=0; i<10; i++){
		cout<<number<<" x " << i<<" = " << number*i<< endl;
	}
	cout<<endl;
}

//вывести таблицу
void print_table()
{
	for (int j=0; j<10;j++){
	for(int i=0; i<10; i++){
		cout<<j<<" x " << i<<" = " << j*i<< endl;
	}
	cout<<endl;
}
}

//меню выбора числа для зубрёжки
void learn_menu()
{
int menu_choice=0;
int yesno=0;
system("cls");
std::cout<<"input number 1-9 to see pifagor tablefor each number. input 0 to see the whole table. input anything else to go back.\nnumber: ";
std::cin>>menu_choice;
//написать функцию для автоматического вывода таблиц
if (menu_choice!=0)
print_ftable(menu_choice);
else print_table();
std::cout<<"continue learning 1 or 0?\n";
cin>>yesno;
if (yesno==1) learn_menu();
else main_menu();
}

//меню выбора числа для проверки
void test_menu()
{
int menu_choice=0;
system("cls");
std::cout<<"input number 1-9 to start testing for each number. input 0 to start the full test. input anything else to go back."<<endl;
std::cin>>menu_choice;
if (menu_choice>=1 && menu_choice<=9)
{
	fragment_test(menu_choice);
}
else if (menu_choice==0)
	full_test();
else main_menu();
}

//проверка отдельных чисел
void fragment_test(int number)
{	system("cls");
int score=0;
int yesno=0;
for (int i=0; i<TESTS_COUNT; i++)
{
	int rand_number=0;
	int answer=0;
	int true_answer=0;
	srand( time( 0 ) );
	rand_number = 1 + rand() % 9;
	cout<<number<< " x " << rand_number<<" = ";
	cin >> answer;
	true_answer=rand_number*number;
	if (answer==true_answer){
	score++;
	cout << "\n\nTHAT'S RIGHT!\nyour score: "<<score<<endl<<endl;
	}
	else cout << "\n\nYOU'VE MISTAKEN!\nyour score: "<<score<<endl<<endl;
}
cout<<"\nyour score: "<<score<<endl;
cout<<"test for this number again?1 or 0"<<endl;
cin>>yesno;
if(yesno==1) fragment_test(number);
else test_menu();
}

void full_test()
{system("cls");
int score=0;
int yesno=0;
for (int i=0; i<TESTS_COUNT; i++)
{
	int rand_number=0;
	int rand_number2=0;
	int answer=0;
	int true_answer=0;
	srand( time( 0 ) );
	rand_number = 1 + rand() % 9;
	rand_number2 = 1 + rand() % 9;
	cout<<rand_number2<<  " x " << rand_number<<" = ";
	cin >> answer;
	true_answer=rand_number*rand_number2;
	if (answer==true_answer){
	score++;
	cout << "\n\nTHAT'S RIGHT!\nyour score: "<<score<<endl<<endl;
	}
	else cout << "\n\nYOU'VE MISTAKEN!\nyour score: "<<score<<endl<<endl;
}
cout<<"\nyour score: "<<score<<endl;
cout<<"test again?1 or 0"<<endl;
cin>>yesno;
if(yesno==1) full_test();
else test_menu();
}

int main(int argc, char *argv[])
{
main_menu();
return 0;
}