Почему не работает код написанный на с++ в Visual Studio ?

#include
#include
#include
#include
#include
using namespace std;
void Drum(int w) {
int v = 0;
int Dollar = 0;
int b = 1 + rand() % 1;
do {
cout << "Enter the number ";
cin >> w;
if (w == b) {
v++;
Dollar += 250000;
cout << "You win" << v << " \ 5 - " << Dollar;
if (v == 5) {
cout << "The game is completed. You won 1.000.000 $ !!!";
exit(0);
}
}
} while (w != b);
cout << "Sorry, you lose...";
}
int main() {
string Yes = "Yes";
string No = "No";
string n;
int v = 0;
int a;
int Dollar = 0;
cout << "Hello, do you want to play Russian roulette? ";
cin >> n;
if (n == No) {
cout << "You refused to play Russian roulette. Good luck!";
}
if (n == Yes) {
cout << "You started a game of Russian roulette. Turn the wheel and shoot the revolver one bullet... \n";
cout << "------------------------";
int b = 1 + rand() % 1;
Drum(a);
}
else {
do {
cout << "To Express more clearly... \n";
cout << "So, your answer? ";
cin >> n;
} while ("Yes" || "No");
if (n == "Yes") {
Drum(a);
}
if (n == "No") {
cout << "You refused to play Russian roulette. Good luck!";
}
}
_getch();
return 0;
}