A total of 55 students participated in the game, and when counted the number of students who participated in A and B game, there were 38 and 42 students respectively. Find how many students participated in both A and B game.
38 42 [OP_ADD] 55 [OP_SUB]
var_a = 38
var_b = 42
var_c = var_a + var_b
var_d = 55
var_e = var_c - var_d
print(int(var_e))