The calendar calculator

[geft]

Input a year and a number. The calculator will tell you what day, date and month that number falls on that year.

Code:

#include <iostream>
#include <string>

using namespace std;
int normal(), leap(), key();
int num, day, date, year, yearc;
int last2digits, keyvalue, centurycode;
string dayc, month;

int main()
{

    cout<< "Enter a year: ";
    cin>> year;

    if (year%4!=0)
    {
        normal();
    }
    else
    {
        leap();
    }

    key();

    cout<< "Day " << num << " falls on " << dayc << ", " << date << " " << month << " " << year<<"\n";
    main();

return 0;
}

int normal()
{
    cout<< "Enter a number between 1 to 365: ";
    cin>> num;

    if (num>=1 && num<=31)
    {
    date=num;
    month="January";
    keyvalue=1;
    }

else if (num>=32 && num<=59)
    {
    date=num-31;
    month="February";
    keyvalue=4;
    }

else if (num>=60 && num<=90)
    {
    date=num-59;
    month="March";
    keyvalue=4;
    }

else if (num>=91 && num<=120)
    {
    date=num-90;
    month="April";
    keyvalue=0;
    }

else if (num>=121 && num<=151)
    {
    date=num-120;
    month="May";
    keyvalue=2;
    }

else if (num>=152 && num<=181)
    {
    date=num-151;
    month="June";
    keyvalue=5;
    }

else if (num>=182 && num<=212)
    {
    date=num-181;
    month="July";
    keyvalue=0;
    }

else if (num>=213 && num<=243)
    {
    date=num-212;
    month="August";
    keyvalue=3;
    }

else if (num>=244 && num<=273)
    {
    date=num-243;
    month="September";
    keyvalue=6;
    }

else if (num>=274 && num<=304)
    {
    date=num-273;
    month="October";
    keyvalue=1;
    }

else if (num>=305 && num<=334)
    {
    date=num-304;
    month="November";
    keyvalue=4;
    }

else if (num>=335 && num<=365)
    {
    date=num-334;
    month="December";
    keyvalue=6;
    }
}

int leap()
{
    cout<< "Enter a number between 1 to 366: ";
    cin>> num;

    if (num>=1 && num<=31)
    {
    date=num;
    month="January";
    keyvalue=0;
    }

else if (num>=32 && num<=60)
    {
    date=num-31;
    month="February";
    keyvalue=3;
    }

else if (num>=61 && num<=91)
    {
    date=num-60;
    month="March";
    keyvalue=4;
    }

else if (num>=92 && num<=121)
    {
    date=num-91;
    month="April";
    keyvalue=0;
    }

else if (num>=122 && num<=152)
    {
    date=num-121;
    month="May";
    keyvalue=2;
    }

else if (num>=153 && num<=182)
    {
    date=num-152;
    month="June";
    keyvalue=5;
    }

else if (num>=183 && num<=213)
    {
    date=num-182;
    month="July";
    keyvalue=0;
    }

else if (num>=214 && num<=244)
    {
    date=num-213;
    month="August";
    keyvalue=3;
    }

else if (num>=245 && num<=274)
    {
    date=num-244;
    month="September";
    keyvalue=6;
    }

else if (num>=275 && num<=305)
    {
    date=num-274;
    month="October";
    keyvalue=1;
    }

else if (num>=306 && num<=335)
    {
    date=num-305;
    month="November";
    keyvalue=4;
    }

else if (num>=336 && num<=366)
    {
    date=num-335;
    month="December";
    keyvalue=6;
    }

}

int key()
{
    last2digits=year;

    for (; last2digits>=100;)
        last2digits-=100;

    yearc=year;
    for (; yearc<1700;)
        yearc+=400;

    for (; yearc>2099;)
        yearc-=400;

    if (yearc>=1700 && yearc<= 1799)
    centurycode = 4;

    else if (yearc>=1800 && yearc<= 1899)
    centurycode = 2;

    else if (yearc>=1900 && yearc<= 1999)
    centurycode = 0;

    else if (yearc>=2000 && yearc<= 2099)
    centurycode = 6;

    day = ((last2digits + last2digits/4 + date + keyvalue + centurycode)%7);


    if (day==0)
    dayc = "Saturday";
    else if (day==1)
    dayc = "Sunday";
    else if (day==2)
    dayc = "Monday";
    else if (day==3)
    dayc = "Tuesday";
    else if (day==4)
    dayc = "Wednesday";
    else if (day==5)
    dayc = "Thursday";
    else if (day==6)
    dayc = "Friday";
}

[mleveill]

cool, i didn't run it though. next, try combining leap() and normal()
e.g.

Code:

get_month(bool leap_year) { ... }

[adeyblue]

Code:

    if (year%4!=0)
    {
        normal();
    }
    else
    {
        leap();
    }

Almost, you need to check whether the year is divisible by 400 as well

    if (year%4!=0 || year % 400 != 0)

1800 wasn't a leap year, but with your current code it is.

[geft]

Thanks for the input. I've always thought a leap year is a year that's divisible by 4.

@mleveill: Thanks for that, but I haven't get to arguments yet. Not sure how to use it.