万年历

#include<iostream>
using namespace std;

int isLeapYear(int year)
{

if (year % 100 == 0 && year % 400 == 0 || (year % 4 == 0 && year % 100 != 0))
{
return 1;
}
else
return 0;
}

int monthDays(int year,int month)
{
int n[12] = { 31,28,31,30,31,30,31,31,30,31,30,31 };
if (isLeapYear(year))
n[1] = 29;
return n[month - 1];
}

int dayNumber(int year,int month)
{
int c,i,s = 0;
int n[12] = { 31,28,31,30,31,30,31,31,30,31,30,31 };
if (isLeapYear(year))
n[1] = 29;
for (i = 0; i<month - 1; i++)
{
s = n[i] + s;
}
c = s + 1;
return c;
}

int week(int year, int month, int c)
{
int s;
s = (year - 1 + (year - 1) / 4 - (year - 1) / 100 + (year - 1) / 400 + c) % 7;
return s;
}

int main()
{
int year, month;
int mon,d,k;
while (cin >> year >> month)
{
d=dayNumber(year,month);
mon=monthDays(year,month);
k=week(year, month, d);
cout << "日" << '\t' << "一" << '\t' << "二" << '\t' << "三" << '\t' << "四" << '\t' << "五" << '\t' << "六" << endl;
for (int i = 1; i <= mon; i++)
{
if (i == 1)
{
for (int j = 0; j<k; j++)
{
cout << '\t';
}
}
cout << i << '\t';
if ((i + k) % 7 == 0)
{
cout << endl;
}
}
cout << endl << endl;
}
return 0;
}