b = 36
36 + 36 = 72
36 - 36 = 0
b = 57
57 + 57 = 114
57 - 57 = 0
b = 63
63 + 63 = 126
63 - 63 = 0
b = 10
10 + 10 = 20
10 - 10 = 0