SJ ¨ ALVST ¨ ANDIGA ARBETEN I MATEMATIK
MATEMATISKA INSTITUTIONEN, STOCKHOLMS UNIVERSITET
Line¨ ara koder och Reed-Muller koder
av
Magnus Weiderling
2012 - No 14
MATEMATISKA INSTITUTIONEN, STOCKHOLMS UNIVERSITET, 106 91 STOCKHOLM
Line¨ ara koder och Reed-Muller koder
Magnus Weiderling
Sj¨ alvst¨ andigt arbete i matematik 15 h¨ ogskolepo¨ ang, grundniv˚ a Handledare: Rikard B¨ ogvad
2012
n
A ={s1, s2, . . . , sq}
q A
q n A = x1x2. . . xn
xi 2 A i 1 i n (x1, . . . , xn)
q n A C q
n
C C
C C |C|
M
R(C) C n logqn|C|
C M = qn
q n n = logq M = log M/log q
C
q n
A =F2={0, 1}
0 1 q = 2
C1={00, 01, 10, 11} n = 2 |C| = 4 C2={000, 011, 101, 110} n = 3 |C| = 4
F3={0, 1, 2} F4
q
q Fq
q Fq
n A
= x1. . . xn = y1. . . yn ( ) =Pn
i=1d(xi, yi)
xi yi 1
(xiyi) =
⇢ 1 xi6= yi
0 xi= yi
C
C d(C)
(C) = {d( ) : 2 6= }
C1 = {00, 01, 10, 11}
x = 00 y = 11 x y
d(x, y) = 1 + 1 = 2 C1 d(C1) = 1
n M d (n, M, d)
n, M d
0)
C ={000, 010, 111} wt(010) = 1
q
q
p p < 12
q 1
{0, 1}
(1 | 0 ) = (0 | 1 ) = p
C
p Mr
Mr c c2 C
Mc
Mr Mc
(Mr Mc = max Mr c 2 C
Mr Mc
d(Mr, Mc)
d(Mr, Mc= min{d(Mr, c) 2 C
p < 12
C Mr
n n 0 i n
d(Mr, c) = i, P Mr pi(1 p)n i p < 12
p0(1 p)n> p1(1 p)n 1> ... > pn(1 p)0
Mr
2 C Mr
d(Mr, c)
u C
u u
u
u (u + 1)
C ={00000, 00111, 11111}
1
C 1
2
00111 11111
C u
d(C) u + 1
d(C) u+1 2 C 1 d( ) u
2 C/ u d(C) 1 < d(C) C u
d(C) < u + 1 d(C) u 1 2 2 C
1 d 1 2) = d(C) u 1
d(C) 2 C
C u
v C
v v C
v v (v + 1)
C ={000, 111}
000 100, 010
001 000
111 110, 101
011 111
C 1
C v d(C)
2v + 1
d b(d 1)/2c
( d(C) 2v + 1
v d( ) v
02 C 6= 0
d( 0, ) d( 0, ) d( , )
d( 0 ) d( 2v + 1 v = v + 1 > d(
C v
) C v d(C) < 2v + 1
0 2 C d( 0 = d(C) 2v v
C v d(C) 2v + 1
d( 0 < v + 1 0
v
0 2 C C v
d( 0 v+1 0
d = d(C) v + 1 d 2v
x1. . . xv
| {z }
lika som c0
xv+1. . . xd
| {z }
lika som c
xd+1. . . xn
| {z }
lika som c0 och c
d( 0 ) = d v v = d( d( 0 ) <
d( d( 0 = d(
0
V Fq
{e1, . . . , er} V
a1e1+ ... + arer= 0) a1= ... = ar= 0
S V Fq S ={e1, e2, . . . , ek}
V < S >
< S > ={(a1e1+· · · + akek) : ai2 Fq}
S < S > {0}
q = 2 S = {0001, 0010, 0100}
< S > ={0000, 0001, 0010, 0011, 0100, 0101, 0110, 0111}
V Fq
S ={e1, . . . , ek} V V V = < S > S
V Fq
V Fq
dim Fq(V )
= (v1, . . . , vn)
= (w1, . . . , wn)2 Fnq
· v1·w1+...+vn·wn2 Fq
· = 0 Fnq Fnq
n Fq S? S
S? { 2 Fnq : · = 0 2 S}
S S?=Fnq
n Fq
C n Fq
Fnq
C n k Fq
[n, k] [n, k, d] d
M k (n, M ) = (n, qk) C
(e1, ..., ek)
(a1e1+ ... + akek) ai Fq q
C qk
k = logqqk= logqM
C1={000000, 100000, 010000, 110000}
C2={000000, 111000, 000111, 111111}
C1 q = 2 4 = 22 6 k = 2
1, 1 2 1
C2 k = 2 3, 3 6
3
3 1
C Fnq C C?
C Fnq
d(C) C
C Fq d(C) = wt(C) wt(C)
C d( = wt(
d(C) 0 0 2 C
d( 0 0) = d(C)
d(C) = d( 0 0) = wt( 0 0 wt(C) 0 0 2 C
2 C { } wt(C) = wt(
wt(C) = wt( ) = d( d(C)
S
Fnq S
S
C
q = 3 C = < S >
S ={12101, 20110, 01122, 11010}
0 BB
@
1 2 1 0 1 2 0 1 1 0 0 1 1 2 2 1 1 0 1 0
1 CC A !
0 BB
@
1 2 1 0 1 0 2 2 1 1 0 1 1 2 2 0 2 2 1 2
1 CC A !
0 BB
@
1 2 1 0 1 0 1 1 2 2 0 0 0 0 1 0 0 0 0 0
1 CC A
C G
C G C
C [n, k] k⇥ n
k n
n k
k k 1
k + 1
H
H C
C?
C [n, k] (n k)⇥
n
C u C uHT = 0
m C
G H
(Ik|X) Ik
k⇥k X G
|
(Y|In k)
Y H
H
G C
G C
C [n, k] Fq G
2 Fnq C?
G 2 C?, GT =
(n k)⇥ n H H
C H HGT =
i i G i2 C 1 i k
2 C
= 1 1+ ... + k k 1, . . . , k2 Fq
2 C? · = 0 2 C i
1 i k GT =
· i= 0 1 i k = 1 1+...+ k k 2
C
· = 1( · 1) +· · · + k( · k) = 0
H C
H H C?
HGT =
HGT = H
C? H
(n k) C?
H C
G = (Ik|X)
C H = ( XT|In k) C
HGT = 0
n k H
XT = XT X
C H
C
C d d 1 H
C d H d
= (v1, ..., vn)2 C e > 0 i1, ..., ie vj = 0 j
2 {i/ 1, ..., ie} i 1 i n i H
C = (v1, ..., vn) e
vi1, ..., vie
= HT vi1 Ti1 vie Tie
e H ci1, ..., cie
C
d C
d 1 d 1
H (i)
C
d C
d H
d (ii)
C
H = 0
@ 1 0 1 0 0 1 1 0 1 0 0 1 0 0 1
1 A
H 0
d(C) = 3
C [n, k, d] Fq
C C qk
( 1, ..., k)
= u1 1+ ... + uk k u1, ..., uk2 Fq
G C i
i = (u1, ..., uk)2 Fkq
= G = u1 1+ ... + uk k C
2 C = G = (u1, ..., uk)2 Fkq
2 Fkq = G
C (5, 3)
G(5,3)= 0
@ 1 0 1 1 0 0 1 0 1 1 0 0 1 0 1
1 A
= 101
= G = (101) 0
@ 1 0 1 1 0 0 1 0 1 1 0 0 1 0 1
1 A =
= 1 + 0 + 0, 0 + 0 + 0, 1 + 0 + 1, 1 + 0 + 0, 0 + 0 + 1 = 1, 0, 0, 1, 1
1 3
C n
Fnq 2 Fnq n
C
C+ ={( + ) : 2 C} (= + C) q = 2 C ={000, 101, 010, 111}
C + 000 ={000, 101, 010, 111}
C + 001 ={001, 100, 011, 110}
C + 010 ={010, 111, 000, 101}
C + 011 ={011, 110, 001, 100}
C + 100 ={100, 001, 110, 011}
C + 101 ={101, 000, 111, 010}
C + 110 ={110, 011, 100, 001}
C + 111 ={111, 010, 101, 000}
C + 000 = C + 010 = C + 101 = C + 111 = C C + 001 = C + 011 = C + 100 = C + 110 =F32 C
C 2 C
= 2
+C = 2 C
+C =
q = 2 C ={0000, 1011, 0101, 1110}
w = 1101 0101
C + 0000 ={0000, 1011, 0101, 1110}
C + 0001 ={0001, 1010, 0100, 1111} (= C + 0100) C + 0010 ={0010, 1001, 0111, 1100}
C + 1000 ={1000, 0011, 1101, 0110}
w = 1101
u = 1000 w u = 1101 1000 =
1101 + 1000 = 0101
C + 0000
n n
C [n, k, d] Fq
H C 2 Fqn
) = HT 2 Fqn k
H
C C =
{0000, 1011, 0101, 1110}
G =
✓ 1 0 1 1 0 1 0 1
◆
S( ) = HT
0000, 0001, 0010 1000
C HGT =
H =
✓ 1 0 1 0 1 1 0 1
◆
S( )
S( )
q = 2 C = {0000, 1011, 0101, 1110}
= 1101 S( ) = HT = 11
1000 = 1101 1000 = 0101
n, M d n M d
q C
(n, M, d) C (C) = (d 1)/n
d/n
R(C) = lognqM
C ={00 . . . 0| {z }
n
, 11 . . . 1| {z }
n
} Fq
(n, M, d) = (n, 2, n) [n, k, d] = [n, 1, n]
M = 2
k = dim(C) = logq(M ) = log2(2) = 1
log2(2)
n = n1 ! 0 n! 1 (C) = n 1n ! 1 n! 1
R(C)
A q (q > 1)
n d Aq
M (n, M, d) A
Aq(n, d) = max{M : (n, M, d) A}
(n, M, d) C M = Aq
qk q n
d Bq(n, d) qk
[n, k, d] Fq
Bq(n, d) = max{qk: [n, k, d] Fq}
Aq(n, d) Bq(n, d) Aq(n, d)
q = 2 C C
C Fq C
C ={(c1, ..., cn, Pn
i=1(ci)) : (c1, ...cn)2 C}
q = 2 Pn
i=1(ci) =Pn i=1(ci)
C ={000, 111, 011, 100}
[3, 2, 1] C
P3
i=1(ci) = 0 + 0 + 0 = 0 P3
i=1(ci) = 1 + 1 + 1 = 1 P3
i=1(ci) = 0 + 1 + 1 = 0 P3
i=1(ci) = 1 + 0 + 0 = 1
C ={0000, 1111, 0110, 1001} [4, 2, 2]
Aq(n, d)
q > 1 n, d 1 d n
qn Pd 1
i=0(ni)(q 1)i Aq
Aq(n, d) Bq(n, d)
A q, q > 1
2 An A n r 0
r
SA( , r) ={ 2 An: d( ) r}
An
q > 1 n r 0 Vqn(r)
Vqn(r) =
⇢ n
0 + n1 (q 1) + n2 (q 1)2+ ... + nr (q 1)r 0 r n
qn n r
r 0 An r
Vqn(r) A q > 1
2 An 2 An
d( , ) = m An m
m
n
m q 1
m mn (q 1)m
0 r n
n r SA( , r) = An Vqn(r) = qn
q > 1 n d 1 d n
Aq(n, d) Pb(d 1)/2cqn i=0 (ni)(q 1)i
b(d 1)/2c (d 1)/2
C = { 1 2 M} (n, M, d)
A A q M = Aq(n, d)
e = b(d 1)/2c SA( i, e) An
SM
i=1SA( i, e)✓ An
|An| = qn
|SA( i, e)| = Vqn(e) i
M · Vqn(e) qn =) Aq(n, d) = M Vqnn
q(e) = Vn qn q(b(d 1)/2c)
q
qn Pb(d 1)/2c
i=0 (ni)(q 1)i
r 2
n = 2r 1 H
Fr2 2r 1 Ham(r, 2)
Ham(3, 2)
[7, 4, 3] 7 4
7 3
47
G G
GHam(3,2)= 0 BB
@
1 0 0 0 1 1 0 0 1 0 0 0 1 1 0 0 1 0 1 1 1 0 0 0 1 1 0 1
1 CC A
HHam(3,2)= 0
@ 1 0 1 1 1 0 0 1 1 1 0 0 1 0 0 1 1 1 0 0 1
1 A
HHam(3,2) GHam(3,2) I4
HHam(3,2) I7 4 = I3
GHam(3,2) HHam(3,2)
(i)
(ii) Ham(r, 2) k = 2r 1 r
(iii) Ham(r, 2) 3 1
(iv) (i)
(ii) H Ham(r, 2) 2r 1 r⇥
(2r 1) 2r 1 r
(iii) H
H H
1 0 . 0
0 1 . 0
1 1 . 0
Ham(r, 2)
3 1
(iv)
Ham(r, 2)
|C| = Pb(d 1)/2cqn
i=0 (ni)(q 1)i = 1+n2n q = 2 d = 3 n = 2r 1
|C| = 1+222rr11 = 22r 1 r
2k (ii)
Ham(r, 2) 1 2r
2r (= n + 1) n
1 n + 1 j
j
j jHT j
H H
( ) = HT ) = 0
6= 0 j 1 j 2r 1
j
j j
Ham(3, 2)
= 1001001
HT = 010 H
2= 0100000 + 2= 1101001
Ham(r, 2) Ham(r, 2)
Ham(r, 2)
2r 1 r
2r Ham(r, 2) 2r2r1 r1 ) Ham(r, 2)
(n, M, d) C Fq
R(C) = lognqM (C) =d 1n
M n
d Aq(n, d) q, n
d Aq(n, d)
= x1...xn = y1...yn
[ = (x1. . . xny1. . . yn)
Ci [n, ki, di] Fq
i = 1, 2 C ={( + ) : 2 C1, 2 C2}
[2n, k1+ k2, min{2d1, d2}] Fq
D [n, k, d] C
C ={( ) : 2 D} [ {( , + ) : 2 D}
[2n, k + 1, min{n, 2d}]
C1= D C2={ , }
0, 8 0, 2
0, 8 log2(1/0, 8) + 0, 2
log2(1/0, 2)⇡ 0, 722
V = 0
S = 1 L1 = 0, 2·
1 + 0, 8· 1 = 1 0, 722 N
0, 722N 2
V V = 0 V S = 10 SV = 110 SS = 111 L2 = 0, 64· 1 + 0, 16· 2 + 0, 16 · 3 + 0, 04 · 3 = 1, 56
N/2 L2N/2 = 0, 78N
3 8
= 2, 184 0, 728N 0, 722
RM (r, m)
RM (1, 5)
RM (1, 5) 25= 32
16 7 15
r m
0 r m r RM (r, m)
[2m, m0 + m1 + ... + mr , 2m r] r = 1
r > 1
r = 0
(RM (0, m))
0 RM (0, m) m 0
{0...0, 1...1} 2m
0 2m
(RM (1, m), )
RM (1, m)
m 1
(i) RM (1, 1) =F22={00, 01, 10, 11}
(ii) m + 1 2 RM (1, m + 1) =
{( ) : 2 RM(1, m)} [ {( + ) : 2 RM(1, m)}
(RM (1, 2) )
(ii) = 00
{00, 00} [ {00, 11} 0000 0011
RM (1, 1) 8 RM (1, 2)
0000 0011 0101 0110 1001 1010 1100 1111
[4, 3, 2]
RM (1, 2)
GRM (1,2)= 0
@ 1 1 1 1 0 1 0 1 0 0 1 1
1 A
(RM (1, 3) ) RM (1, 3) 16
00000000 00001111 00110011 00111100 01011010 01010101 01100110 01101001 10010110 10011001 10100101 10101010 11000011 11001100 11110000 11111111 [8, 4, 4]
4
m 1 RM (1, m) [2m, m + 1, 2m 1]
0 1 2m 1
RM (1, 1) [2, 2, 1]
RM (1, m) RM (1, m 1)
RM (1, m 1)
2m 1, m, 2m 2] RM (1, m)
2· 2m 1, m + 1, min{2 · 2m 2, 2m 1}] = [2m, m + 1, 2m 1]
RM (1, m + 1)
2(m+1) 1 = 2m RM (1, m + 1)
RM (1, m) 2 RM(1, m)
2m 1 2m 1+ 2m 1= 2· 2m 1= 2m
2 RM(1, m)
2m 1 = 22m RM
2m 1 2m
= 0 = 1 2m
= 1 = 0 2m
RM (1, 2)
22 1 = 2 1
RM (1, 3) 23 1= 4 1
RM (1, m+
1) RM (1, m)
(i) RM (1, 1) GRM (1,1)
✓ 1 1 0 1
◆
(ii) GRM (1,m) RM (1, m)
RM (1, m + 1) GRM (1,m+1)=
✓ GRM (1,m) GRM (1,m) 0...0 1...1
◆
GRM (1,2)
RM (1, 3)
GRM (1,3) 0 BB
@ 1 x1
x2
x3
1 CC A
0 BB
@
1 1 1 1 1 1 1 1 0 0 0 0 1 1 1 1 0 0 1 1 0 0 1 1 0 1 0 1 0 1 0 1
1 CC A
RM (1, 3)
k =
✓ m 0
◆ +
✓ m 1
◆ +
✓ m 2
◆ +· · · +
✓ m r
◆
= 4 r = 1 m = 3
4 Muc= (a0a1a2a3)
ai Mc =P3
i=0aiGRM (1,3)i GRM (1,3)i i
Muc= 1010 RM (1, 3)
Mc= 1· (11111111) + 0 · (00001111) + 1 · (00110011) + 0 · (01010101) =
= 11111111 + 00110011 = 11001100 Mc
Muc
1
RM (1, 3)
= x1. . . xn = y1. . . yn
x y
\ = (x1· y1. . . xn· yn)
\ 1 i 1 i
x1, . . . , xm
xi1xi2. . . xis xi x1, . . . , xm
xixj = xjxi
x2i = xi
p(x1, . . . , xm) Z2
0
1 m = 3 2·2·2 = 8
p(x1, x2, x3) = 1· x1+ 1· x2+ 0· x3
x1 x2 x3 p
0 0 0 0
0 0 1 0
0 1 0 1
0 1 1 1
1 0 0 1
1 0 1 1
1 1 0 0
1 1 1 0
p
ap= 00111100 RM
00000000 11111111
(RM (r, m))
0 r m r
ap n = 2m
p(x1, ..., xm) r
RM (1, 3) r = 1 m = 3 n = 23= 8
{1, x1, x2, x3} 1 x1, x2
x3
p(x1, x2, x3) 1
p(x1, x2, x3) = a01 + a1x1+ a2x2+ a3x3
ai= 0 1
a0(11111111) + a1(00001111) + a2(00110011) + a3(01010101)
16 a0 = 0 a1= 1 a2= 1 a3= 0
x1+ x2 00001111 + 00110011 = 00111100
k
S k Zm2 m
S b + S b2 Zm2 dim(S) = k b + S
k
S
H S
x2 S () xHT = 0
x2 b + S () x b2 S (x b)HT = 0
x2 b + S xHT = bHT
Zm2
EG(m, 2) m Z2
dim(S) = 0 b + S 0
b+{0} = {b} EG(m, 2)
EG(m, 2) 1
{b, b + c} c2 Zm2 {0}
Z22 EG(2, 2)
22= 4 0 42 = 6 1
EG(3, 2) 23= 8 0 82 = 28 1
8
3 / 43 = 14 2
8 EG(3, 2)
ap=
EG(3, 2) ap ap
1 F = 2
RM (1, m) m 3
k = m 1
m = 1, k = 0 RM (1, 1) = Z12 EG(1, 2)
21= 2 22 = 1
0 RM (1, 1)
m = 2 RM (1, 2) = Z22
EG(2, 2) (22) = 4 42 = 6
1 RM (1, 2)
m = 3 RM (1, 3) 14
2
F E EG(m, 2) aF · aE ⌘ |F \ E|
mod 2
|F | F = 0
0 1 aF · aE ⌘
wt(aF \ aE) = wt(aF\E) =|F \ E|
F = + S E = + T EG(m, 2)
Zm2 F \ E = ; F \ E = + (S \ T )
F \ E
F \ E = ; F \ E 6= ; x
F \ E x + r2 F \ E r2 S \ T
y F\ E x + r r2 S \ T
x = b + s x2 b + S r2 S \ T
S x + r = b + (s + r) 2 b + S
s + r2 S x + r2 c + T
x + r b + S c + T F \ E
y F \ E x = b + s
y = b + s1 x y S x y2 T
x y2 T \ S x y r y = x + r
0
RM (r, m)
p(x1, . . . , xm) = Xr s=0
X
i1,...,is
ai1,...,isxi1. . . xis= a0+ a1x1+· · · + a12x1x2+ . . .
r
ap= Xr s=0
X
i1,...,is
ai1,...,isaxi1...xis
axi1...xis xi1· · ·
xis ax1x2= x1· x2
p(x1, . . . , xm)
ap
r > 1 r, r 1, r 2
RM (1, 3) r = 1, m = 3
ap= a01 + Xm i=1
aiaxi
{k}c={j1, . . . , jm 1}
{1, . . . , m} {1, 2, 3}
RM (1, 3) {k} = {3} {k}c={1, 2}
ap· axj1···xjm 1
ap
axi· axj1...xjm 1 ⌘ |Fxi\ Fxj1...xjm 1| mod 2 ⌘ |Fxixj1...xjm 1| mod 2
Fx1 x1
0 Fxixj1...xjm 1 0
{i, j1, . . . , jm 1} = {1, . . . , m}
{i} = {j1. . . jm 1}c={k}
RM (1, 3) {k} = {3}
{3} = {1, 2}c={3}
ap· axj1...xj2 = ai
ap· ab+Fxj1 ...xj2
b + Fxj1...xj2 Fxj1...xj2
axi· ab+Fxj1 ...xj2 ⌘ |Fxi\ (b + Fxj1...xj2)| mod 2
|Fxi\ (b + Fxj1...xj2)| = 1 2 Fxi\ (b + Fxj1...xj2)
Fxi\ (b + Fxj1...xj2) = + (Fxi\ Fxj1...xj2) = + Fxixj1...xj2
0 Fxixj1...xjm 1
ap· ab+Fxj1 ...xjm 1 = ai
{j1. . . jm 1} = {k}c b EG(3, 2)
2m 1 1
Fxj1...xj2
2m 1 4 RM (1, 3) ai
(2m 1 1)/2
RM (1, 3)
1 x1 x2 x3 x1· x2 x2· x3 x1· x3
1 0 0 0 0 0 0
1 0 0 1 0 0 0
1 0 1 0 0 0 0
1 0 1 1 0 1 0
1 1 0 0 0 0 0
1 1 0 1 0 0 1
1 1 1 0 1 0 0
1 1 1 1 1 1 1
RM (1, m)
1 2m 1
a0
RM (1, 3) Mc= (c0c1...c7)
Mr = (r0r1...r7) Me = (e0e1...e7)
Mr= Mc+ Me ap
Mc = 00111100
Mr= 10111100 Mc {010, 011, 100, 101}
Mc= (a0a1a2a3)GRM (1,3)= a01 + a1x1+ a2x2+ a3x3
a0, a1, a2 a3
ax1x2 Fx1x2 ={110, 111}
ax2x3 Fx2x3 ={011, 111}
ax1x3 Fx1x3 ={101, 111}
a3 k = 3 {k}c={1, 2}
Fx1x2
{110, 111}
{100, 101}
{010, 011}
{000, 001}
a3= ap· ab+Fxj1 ···xj2
10111100· 00000011 = 0 10111100· 00001100 = 0 10111100· 00110000 = 0 10111100· 11000000 = 1
a3 0
a2= a1= 1 a0
Mr a1a2a3· GRM (1,3)2,3,4= 10111100 110· GRM (1,3)2,3,4
= 10111100 00111100 = 10000000 = a0· 1 + Me
a0 1 01111111 a0 0
10000000 a0= 0
0 1
0, 1, 1 0
Muc= 0110 Me
Mr= 10111100 Mr Me= Mr+ Me= 00111100
RM (0, 1) 00 11
RM (1, 1) 00 01 10 11
RM (1, 2) 0000 0011 0101 0110 1001 1010 1100 1111
RM (1, 3)
00000000 00001111 00110011 00111100 01011010 01010101 01100110 01101001 10010110 10011001 10100101 10101010 11000011 11001100 11110000 11111111
RM (1, 4)
0000000000000000 0000000011111111 0000111100001111 0000111111110000 0011001111001100 0011001100110011 0011110000111100 0011110011000011 0110011010011001 0101101010100101 0110100110010110 0101010110101010 0101010101010101 0101101001011010 0110100101101001 0110011001100110 1111000000001111 1111000011110000 1100110011001100 1001011010010110 1100001100111100 1100001111000011 1100110000110011 1010101010101010 1001100110011001 1010010110100101 1010101001010101 1001100101100110 1010010101011010 1001011001101001 1111111100000000 1111111111111111
A a0
c C
C
C C
d(x, y) x y
d
d(C) C
e1
Fq
F G H
Ik k⇥ k
k m
M =|C| C
Muc
Mc
Mr
Me
n p
q A
R(C) C
< S > S
si i A
ri i
v v w
wt(x) x
x y b c