We want to share the books that Yoongi, Eunji, and Yuna had together fairly. If Yoongi gives 5 books to Eunji and receives 15 books from Yuna, and Eunji gives 10 books to Yuna, the three of them will each have 45 books. How many books did Yunji bring at first?
45 15 [OP_SUB] 5 [OP_ADD]
var_a = 45
var_b = 15
var_c = var_a - var_b
var_d = 5
var_e = var_c + var_d
print(int(var_e))