n1=1; //initial state
n2=3; //final state
E= -13.6; //energy in ground state, eV
 
dE= E*((1/n2^2)-(1/n1^2)); //Change in energy, eV
disp(dE,"The energy change of Hydrogen atom, in eV, is: ")
 
//Result
// The energy change of Hydrogen atom, in eV, is:    
//   12.088889