public class Main {
public static void main(String[] args) {
int sum = 0;
for (int i = 1; i <= 2020; i++) {
String ls = i + "";
for (int j = 0; j < ls.length(); j++) {
if (ls.charAt(j) == '2') {
sum++;
}
}
}
System.out.println(sum);//624
}
}