//Variable declaration
Na=5*10**23
Nd=3*10**23
ni=2*10**16
//Calculations
p=((Na-Nd)+(Na-Nd))/2

//Result
printf('p = %0.3f    *10**23 m**-3 \n',p*10**-23)
printf('The electron concentration is given by n = %0.3f   *10**9 m**-3  \n',ni**2/p*10**-9)