#! /usr/bin/calc

define x1(t) {return cos(t)-300;}
define x2(t) {return sin(t)+450;}
define x3(t) {return 1/(power(x1(t),2)+power(x2(t),2));}

define dx1(t) {return -sin(t);}
define dx2(t) {return cos(t);}
define dx3(t) {return (2*x1(t)*dx1(t) + 2*x2(t)*dx2(t))/power(power(x1(t),2)+power(x2(t),2),2); }

define H(t) {return re(
		sqrt(
		power(dx1(t),2) + power(dx2(t),2) + power(dx3(t),2)
		));}

define v(x) {return re(power(x1(x),2)+power(x2(x),2));}
define dv(x) {return re(2*x1(x)*dx1(x) + 2*x2(x)*dx2(x)) ;}
define u(x) {return re(dv(x)/power(v(x),2)) ;}
define h(x) {return re(sqrt(re(1 + power(u(x),2)))) ;} 


define riemann(inicio, fim,delta){
	local soma = 0;
	local x=inicio;
	while(x<fim){
	soma = soma + h(x);
	x +=delta;
	}
	return(soma*delta);
}


pi=4*atan(1)
print riemann(0,2*pi,0.0005)