calender.cpp

#include "pthread.h"
#include "iostream"
#include "stdio.h"
#include "stdlib.h"
#include "unistd.h"
#include "bits/stdc++.h"
#include "ctime"
#include "cstdlib"

using namespace std;
int dayNumber(int day, int month, int year)
{
    static int t[] = { 0, 3, 2, 5, 0, 3, 5, 1,
                       4, 6, 2, 4 };
    year -= month < 3;
    return (year + year / 4 - year / 100 +
        year / 400 + t[month - 1] + day) % 7;
}

int numberOfDays(int monthNumber, int year)
{

    // January
    if (monthNumber == 0)
        return (31);

    // February
    if (monthNumber == 1)
    {
        // If the year is leap then February has
        // 29 days
        if (year % 400 == 0 ||
            (year % 4 == 0 && year % 100 != 0))
            return (29);
        else
            return (28);
    }

    // March
    if (monthNumber == 2)
        return (31);

    // April
    if (monthNumber == 3)
        return (30);

    // May
    if (monthNumber == 4)
        return (31);

    // June
    if (monthNumber == 5)
        return (30);

    // July
    if (monthNumber == 6)
        return (31);

    // August
    if (monthNumber == 7)
        return (31);

    // September
    if (monthNumber == 8)
        return (30);

    // October
    if (monthNumber == 9)
        return (31);

    // November
    if (monthNumber == 10)
        return (30);

    // December
    if (monthNumber == 11)
        return (31);
    return 0;
}

int main()
{
    int year;
    cout << "Enter Year:";
    cin >> year;
    cout << "\e[1;32m\tCalendar for " << year << "\n";
    int days;
    int current = dayNumber(1, 1, year);
    for (int i = 0; i < 12; i++)
    {
if(i==0)
{
cout<<"JAN"<<endl;
}
else if(i==1)
{
cout<<"FEB"<<endl;
}
else if(i==2)
{
cout<<"MAR"<<endl;
}
else if(i==3)
{
cout<<"APR"<<endl;
}
else if(i==4)
{
cout<<"MAY"<<endl;
}
else if(i==5)
{
cout<<"JUN"<<endl;
}
else if(i==6)
{
cout<<"JUL"<<endl;
}
else if(i==7)
{
cout<<"AUG"<<endl;
}
else if(i==8)
{
cout<<"SEP"<<endl;
}
else if(i==9)
{
cout<<"OCT"<<endl;
}
else if(i==10)
{
cout<<"NOV"<<endl;
}
else if(i==11)
{
cout<<"DEC"<<endl;
}
        days = numberOfDays(i, year);
        cout << "\e[1;32m  Sun  Mon  Tue  Wed  Thu  Fri  Sat\n";
        int k;
        for (k = 0; k < current; k++)
            cout << "    ";

        for (int j = 1; j <= days; j++)
        {
            printf("%4d", j);
            if (++k > 6)
            {
                k = 0;
                cout << "\n";
            }
        }

        if (k)
            cout << "\n";
        current = k;
    }

    return 0;
}