Cours - LIFL

(S, A)S
A S A ⊂S×S
(a, b) (b, a)A G
(v, w)v w (v, w)
v→w vw
(v, w)v w w v
v v w
0
(S, A)S
A S
A G {a, b}
{b, a} {v, w}v−w vw
v w {v, w}A v
w
v w v0v1, v1v2, ..., vk−1vkv0=v
vk=w k 0w
v v w
v0v1, v1v2, ..., vk−1vkv0=vk
k > 1v0v1, v1v2, ..., vk−1vkv0=vk
v0v1, v1v0
a b
a b a b

a b
G= (S, A)G0= (S0, A0)S0⊂S A0⊂A
A0S0
g
(S, A, P ) (S, A)P
(S, A, P ) (S, A)W
G= (S, A)n p A S ={v1, ..., vn}
0≤p≤n20≤p≤n(n+ 1)/2
•
n×n A =
(aj
i),1≤i≤n, 1≤j≤n
aj
i= 1 si vivj∈A
= 0 sinon
aj
i=ai
j
n2p
vivj
aj
ivivj
•
s
s v (s, v)
A
n∗p
vivjvi