ZOJ 1049 (I Think I Need a Houseboat)

#include <iostream>
#include<cmath>
const double PI=3.14159;
int main()
{
    using namespace std;
    double x,y,r_2;
    int N,i=1,year;
    cin>>N;
    while(N--)
    {
        cin>>x>>y;
        r_2=x*x+y*y;
        year=int(ceil((PI*r_2)/2/50));
        cout<<"Property "<<i<<": This property will begin eroding in year "<<year<<".\n";
        i++;
    }
    cout<<"END OF OUTPUT.\n";
    return 0;
}