Students rode the 15-seater ride once over 18 times. If each ride has 3 empty seats, what is the total number of students?
15 3 [OP_SUB] 18 [OP_MUL]
var_a = 15
var_b = 3
var_c = var_a - var_b
var_d = 18
var_e = var_c * var_d
print(int(var_e))