You want to divide 20 apples into 2 different baskets. There should be at least 1 apple in the basket. How many ways are possible to divide apples?
20 2 [OP_SUB] 1 [OP_ADD]
var_a = 20
var_b = 2
var_c = var_a - var_b
var_d = 1
var_e = var_c + var_d
print(int(var_e))