使用DES s-box，并借助图1，显示S5（18）= d，S6（09）= 7，S7（12）= c和S8（3d）= 6

Question

使用DES s-box，并借助图1，显示S5（18）= d，S6（09）= 7，S7（12）= c和S8（3d）= 6。 有人可以帮忙回答这个问题吗？我只是不明白

Answer 1

S5（18）= d

18 (hex) = 00011000 (Binary)

outer=00        row 0

inner=1100      col 12

S5 row 0    col 12 = 13

13 in hex = d

S6（09）= 7

09 (hex) = 00001001 (Binary)

outer=  01      row 1

inner= 0100column 4

s6 row 1    column 4 =7
7 in hex = 7

S7（12）= c

12 (hex) =  010010 (Binary)

outer = 00      row 0
inner = 1001    Column 9

S7 row 0        column 9 = 12

12 in hex = c

S8（3d）= 6

3d= 00111101

outer = 11      row 3
inner = 1110    column 14

S8 row 3    column 14 = 6
6 in hex =6