Date: 1998jan20 Updated: 2019may30 Language: C/C++ Q. C/C++: When is tomorrow? A. Sometimes C/C++ is so nice. Say you want to find tomorrow's date. Do you need to make a table holding the number of days in each month - and what about leap years? Nope, this fairly simple code does the trick:

#include <time.h> #include <stdio.h> const time_t SECONDS_PER_DAY = 60 * 60 * 24; // Returns the date of tomorrow void Tomorrow(int &year, int &month, int &day) { time_t now; struct tm *here; now = time(NULL); // Get the current time here = localtime(&now); here->tm_hour = 12; // Set to noon to handle daylight savings - important here->tm_min = here->tm_sec = 0; now = mktime(here) + SECONDS_PER_DAY; // The key line here = localtime(&now); year = here->tm_year + 1900; month = here->tm_mon + 1; day = here->tm_mday; } main() { int year, month, day; Tomorrow(year, month, day); printf("Tomorrow is %04d-%02d-%02d\n", year, month, day); }