Calculating Easter Sunday

#include <iostream>
#include <string>
#include <cmath>
#include <time.h>
#include <stdio.h>
#include <iomanip>

using namespace std;

int main()
{	
	
	cout<< "Enter year of inquiry"<<endl;		
	int x;//The year for which it is desired to compute Easter Sunday.
	cin>> x;//The 4-digit year.	
	if (x<0001 || x>9999)
		cout<<"The year has to be between 0001 & 9999!"<<endl;
	int a = x % 19;//The remainder of the division of x by 19.
	int b = x % 4;//The remainder of the division of x by 4.
	int c = x % 7;//The remainder of the division of x by 7.
	int d = (19 * a + 24) % 30;//The remainder of the division of (19*a + 24) by 30.
	int e = (2 * b + 4 * c + 6 * d + 5) % 7;//The remainder of the division of (2*b+4*c+6*d+5) by 7.
	int sunday = (22 + d + e);//The calculation of easter sunday.
	int month = 3; // March
    if(sunday > 31)
    {
        month = 4;
        sunday -= 31;
    }


	cout<<setw(4)<< "Day" <<setw(8)<< "Month" <<setw(8)<< "Year"<<endl;
	cout<<endl;
	cout<<"--------------------"<<endl;
	cout<<endl;
	cout<<setw(4)<<sunday<<setw(6)<<month<<setw(10)<<x<<endl;
	
	
	return 0;
}