xiao hai mo ji ga #include <iostream> #include <vector> using namespace std; int main() { int year, month, day; cin >> year >> month >> day; vector<int> days = {31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31}; bool is_leap_year = (year%4 == 0 &...