#!/usr/local/bin/calc
global n,h,c,k,T,PI,UPPER,LOWER,x,dx,factor,exponent,sum;
h=6.626E-34;
c=3.0E8;
PI=3.1415926;
k=1.38E-23;
UPPER=25.0E-6;
LOWER=0.5E-6;
dx=(UPPER-LOWER)/1000.0;
factor=2.0*PI*h*c*c;
exponent=h*c/k;
printf("T=");
scanf("%f",T);
sum=0.0;
for(n=0;n<1000;n++){
x=LOWER+n*dx;
sum=sum+(factor/(x*x*x*x*x))*dx/(exp(exponent/(x*T))-1.0);
}
printf("%f\t%7.3f\n", T,sum);