define atan(a){
	return a(a)
}
define log_e(a){
	return l(a)
}
define log(a,b){
	return l(b)/l(a)
}
define sin(a){
	return s(a)
}
define cos(a){
	return c(a)
}
define tan(a){
	return s(a)/c(a)
}
define exp(a){
	return e(a)
}
define pow(a,b){
	return e(b*l(a))
}
define fact(n){
	if(n>1) {
		return n*fact(n-1);
	}else{
		return 1;
	}
}

pi = 4*atan(1);