//Given that
lambda = 632.8*10^-9  //in meter
i = 0  //in rad
dFringes = 6
bFringes = 5

//Sample Problem 36-6
printf("**Sample Problem 36-6**\n")
//Assume the difference in thickness is 't'
//then the path difference will be 2*L
//hence
deltaL = bFringes/2*lambda
printf("The difference in thickness is equal to %fnm", deltaL*10^9)