使用C++在终端打印日历

//print calender
#include <iostream>
#include <iomanip>
using namespace std;

void printMonth(int year,int month);
void printMonthTitle(int year,int month);
void printMonthName(int month);
void printMonthBody(int year,int month);
int getStartDay(int year,int month);
int getTotalNumberOfDays(int year,int month);
int getNumberOfDaysInMonth(int year,int month);
bool isLeapYear(int year);

int main()
{
    cout<<"Enter full year(e.g.,2010):";
    int year;
    cin>>year;

    cout<<"Enter month in number between 1 and 12:";
    int month;
    cin>>month;
    printMonth(year,month);
    cout<<endl;
    return 0;
}

void printMonth(int year,int month)
{
    printMonthTitle(year,month);
    printMonthBody(year,month);
}

void printMonthTitle(int year,int month)
{
    printMonthName(month);
    cout<<" "<<year<<endl;
    cout<<"_____________________________"<<endl;
    cout<<" Sun Mon Tue Wed Thu Fri Sat"<<endl;
}

void printMonthName(int month)
{
    switch(month)
    {
        case 1: cout<<setw(16)<<"January"; break;
        case 2: cout<<setw(16)<<"Feruary"; break;
        case 3: cout<<setw(16)<<"March"; break;
        case 4: cout<<setw(16)<<"April"; break;
        case 5: cout<<setw(16)<<"May"; break;
        case 6: cout<<setw(16)<<"June"; break;
        case 7: cout<<setw(16)<<"July"; break;
        case 8: cout<<setw(16)<<"August"; break;
        case 9: cout<<setw(16)<<"September"; break;
        case 10: cout<<setw(16)<<"October"; break;
        case 11: cout<<setw(16)<<"November"; break;
        case 12: cout<<setw(16)<<"December"; break;
    }
}

void printMonthBody(int year,int month)
{
    int startDay=getStartDay(year,month);
    int numberOfDaysInMonth=getNumberOfDaysInMonth(year,month);
    for(int i=0;i<startDay;i++)
    {
        cout<<"    ";
    }
    for(int i=1;i<=numberOfDaysInMonth;i++)
    {
        cout<<setw(4)<<i;
        if((i+startDay)%7==0)
        cout<<endl;
    }
}

int getStartDay(int year,int month)
{
    int startDay1800=3;
    int totalNumberOfDays=getTotalNumberOfDays(year,month);
    return (totalNumberOfDays+startDay1800)%7;
}

int getTotalNumberOfDays(int year,int month)
{
    int total=0;
    for(int i=1800;i<year;i++)
        if(isLeapYear(i))
        total=total+366;
        else
        total=total+365;
    for(int i=1;i<month;i++)
        total=total+getNumberOfDaysInMonth(year,i);
    return total;

}

int getNumberOfDaysInMonth(int year,int month)
{
    if(month==1||month==3||month==5||month==7||month==8||month==10||month==12)
        return 31;
    if(month==4||month==6||month==9||month==11)
        return 30;
    if(month==2) return isLeapYear(year)?29:28;
    return 0;
}

bool isLeapYear(int year)
{
    return year%400==0||(year%4==00&&year%100!=0);
}