Jungkook and Seokjin each had 12 pencils. After using a few of them, Jungkook gave 4 of the remaining pencils to Seokjin, and the number of pencils they both had became 7 each. How many pencils did Seokjin use?
12 7 [OP_SUB] 4 [OP_ADD]
var_a = 12
var_b = 7
var_c = var_a - var_b
var_d = 4
var_e = var_c + var_d
print(int(var_e))