C ++ Perpetual Calendar

// Dateuitl. h

# Ifndef _ dateutil_h _ # DEFINE _ dateutil_h _ # include <iomanip> # include <iostream> # include <string> using namespace STD; Class dateutil {public: int nowtoday (INT year, int month, int day); // The number of days bool inputdayistrue (INT year, int month, int day) from one day to January 1, January 1, 1800 ); // judge whether the input date is valid int finddayweekend (INT year, int month, int day); // find the day of the week int displaymonth (INT year, int month ); // display the calendar int disp of a calendar month of a year Layyear (INT year); // display the calendar PRIVATE: int spacesize of a year; // output length SETW () size bool isleapyear (INT year) {// determine whether it is a leap year return (0 = year % 4 & 0! = Year % 100) | (0 = year % 400);} public: int getmonthdaynumber (INT year, int month) {// return the number of days in a certain year in January int daynumber; If (2 = month) {// February if (isleapyear (year) daynumber = 29; elsedaynumber = 28;} else {If (month <8 & 1 = month % 2) | (month> = 8 & 0 = month % 2 )) // The odd month before December 31, is 31 days, and the even number after December 31 is 31 days daynumber = 31; If (month <8 & 0 = month % 2) | (month >=8 & 1 = month % 2) // 30 days of the even month before January 1, August and 30 days of the odd month after January 1, August daynumber = 30 ;} return daynumber ;};# endif

// Dateutil. cpp

# Include "dateutil. H "int dateutil: nowtoday (INT year, int month, int day) {int diday, I; for (I = 1800, diday = 0; I <year; I ++) // a single leap year + 366 days if (isleapyear (I) diday + = 366; elsediday + = 365; for (I = 1; I <month; I ++) diday + = getmonthdaynumber (year, I); diday + = day-1; return diday;} bool dateutil: inputdayistrue (INT year, int month, int Day) {int turedaynumber; If (year <18 00 | month> 13 | day> 31) {// If the input date is less than January 1, 1800, and later than 31, false return is returned ;} else {turedaynumber = getmonthdaynumber (year, month); // If the input day is greater than the actual day of the month, the system returns the error if (day> turedaynumber) return false;} return true ;} int dateutil: displaymonth (INT year, int month) {int excur, I, totalday; spacesize = 4; excur = (nowtoday (year, month, 1) + 3) % 7; // calculate the day of the month as the day of the week, and then add the number of days on the basis of cout <Year <"year" <month <"month" <Endl; cout <SETW (spacesize) <"day" <SETW (spacesize) <"1" <SETW (spacesize) <"2"; cout <SETW (spacesize) <"3" <SETW (spacesize) <"4" <SETW (spacesize) <"5"; cout <SETW (spacesize) <"6" <Endl; for (I = 1; I <= excur; I ++) cout <SETW (spacesize) <"; // first, output extra spaces totalday = getmonthdaynumber (year, month ); for (I = 1; I <= totalday; I ++) {// then auto-increment. Of course, when the length is greater than seven, wrap cout <SETW (spacesize) <I; If (0 = (I + excur) % 7) // wrap condition cout <Endl;} cout <Endl; return 0;} int dateutil: finddayweekend (INT year, int month, int Day) {// find the day of the week int totalday; char weekend [7] [4] = {"day" },{ "1" },{ "2 "}, {"3" },{ "4" },{ "5" },{ "6" }}; totalday = nowtoday (year, month, day ); cout <year <"year" <month <"month" <day <"Day is a week" <weekend [(totalday + 3)) % 7] <Endl; return 0;} int dateutil: displayyear (INT year) {int I, j, k, n, month1, mon2, month3; // output calendar month1 mon2month3 according to one quarter is the number of days that the month should have int excur1, excur2, excur3; // I, J, K represent the daily value of three months excur1, respectively, excur2, excur3 indicates the offset int sea; char months [12] [10] ={{ "January" },{ "February" },{ "March "}, {"April" },{ "May" },{ "June" },{ "July" },{ "August" },{ "September "}, {"October" },{ "November" },{ "December" }}; spacesize = 3; cout <year <"year" <Endl; fo R (SEA = 1; Sea <= 12; sea + = 3) {// display excur1 = (nowtoday (year, sea, 1) + 3) % 7 in four quarters; // calculate the offset excur2 = (nowtoday (year, sea + 1, 1) + 3) % 7; excur3 = (nowtoday (year, sea + 2, 1) + 3) % 7; month1 = getmonthdaynumber (year, sea); // calculate the number of days in three months, respectively. mon2= getmonthdaynumber (year, sea + 1 ); month3 = getmonthdaynumber (year, sea + 2); // display the three-month week cout <months [sea-1] <SETW (21) <"" <Months [Sea] <SETW (20) <"" <months [sea + 1] <Endl; cout <SETW (spacesize) <"day" <SETW (spacesize) <"1" <SETW (spacesize) <"2"; cout <SETW (spacesize) <"3" <SETW (spacesize) <"4" <SETW (spacesize) <"5"; cout <SETW (spacesize) <"6" <SETW (spacesize) <""; cout <SETW (spacesize) <"day" <SETW (spacesize) <"1" <SETW (spacesize) <"2"; cout <SETW (spacesize) <"3" <SETW (spacesize) <"4" <SETW (spacesize) <"5"; cout <SETW (spacesize) <"6" <SETW (spacesize) <""; cout <SETW (spacesize) <"day" <SETW (spacesize) <"1" <SETW (spacesize) <"2"; cout <SETW (spacesize) <"3" <SETW (spacesize) <"4" <SETW (spacesize) <"5"; cout <SETW (spacesize) <"6" <Endl; For (n = 1; n <= excur1; n ++) // The first line is processed separately. Extra spaces are then cout <SETW (spacesize) <""; // I, j, k separately Save the current date for (N; n <= 7; N ++) cout <SETW (spacesize) <n-excur1; cout <SETW (spacesize) <"; I = N-excur1; for (n = 1; n <= excur2; n ++) cout <SETW (spacesize) <""; for (N; n <= 7; n ++) cout <SETW (spacesize) <n-excur2; cout <SETW (spacesize) <"; j = N-excur2; For (n = 1; n <= excur3; n ++) cout <SETW (Spacesize) <"; for (N; n <= 7; n ++) cout <SETW (spacesize) <n-excur3; cout <Endl; k = N-excur3; while (I <= month1 | j <= mon2|| k <= month3) {// when the three-month date is greater than the expected number of days, the cycle ends for (n = I; I <n + 7; I ++) // output once in the next 7 days. However, if (I <= month1) cout <SETW (spacesize) <I; elsecout <SETW (spacesize) <""; cout <SETW (spacesize) <"; for (n = J; j <n + 7; j ++) if (j <= mon22) cout <SETW (spacesize) <j; elsecout <SETW (spacesize) <"; cout <SETW (spacesize) <""; for (n = K; k <n + 7; k ++) if (k <= month3) cout <SETW (spacesize) <K; elsecout <SETW (spacesize) <"; cout <Endl ;}cout <Endl; return 0 ;}

// Main. cpp

# Include "dateutil. H "int main () {dateutil date; int year, month, day; cout <" Enter year "<Endl; CIN> year; date. displayyear (year); cout <"----------------------" <Endl; cout <"Enter year month" <Endl; CIN> year> month; date. displaymonth (year, month); cout <"----------------------" <Endl; cout <"Enter the year, month, and day" <Endl; cin> year> month> day; date. finddayweekend (year, month, day); Return 0 ;}