There are 5 pens, with all different colors, including a red pen. When two of them are given to Seoyoon and one is given to Jiwoo, find the number of cases where the red pen is given to Seoyoon.
5 1 [OP_SUB] 2 1 [OP_SUB] 1 [OP_ADD] [OP_PERM]
var_a = 5
var_b = 1
var_c = var_a - var_b
var_d = 2
var_e = 1
var_f = var_d - var_e
var_g = 1
var_h = var_f + var_g
var_i = 1
var_c = int(var_c)
var_h = int(var_h)
for i, elem in enumerate(range(var_h)):
    var_i = var_i * (var_c-i)
print(int(var_i))