#include <iostream> #include <vector> using namespace std; int main() { int year, month, day; vector<int> monthcount = {0,31,28,31,30,31,30,31,31,30,31,30 }; for (int i = 1; i < 12; i++) { monthcount[i] += monthcount[i - 1]; } while (cin >> year >> month >> day...