set V = {0 ,1};
set E = {0 };
set S = 0 .--> 0 ;
set T = 0 .--> 1;
A1:
( dom (0 .--> 0 ) = {0 } & dom (0 .--> 1) = {0 } )
by FUNCOP_1:19;
then reconsider S = 0 .--> 0 as Function of {0 },{0 ,1} by A1, FUNCT_2:5;
then reconsider T = 0 .--> 1 as Function of {0 },{0 ,1} by A1, FUNCT_2:5;
set G = createGraph {0 ,1},{0 },S,T;
A2:
( the_Vertices_of (createGraph {0 ,1},{0 },S,T) = {0 ,1} & the_Edges_of (createGraph {0 ,1},{0 },S,T) = {0 } & the_Source_of (createGraph {0 ,1},{0 },S,T) = S & the_Target_of (createGraph {0 ,1},{0 },S,T) = T )
by GLIB_000:8;
take
createGraph {0 ,1},{0 },S,T
; :: thesis: ( not createGraph {0 ,1},{0 },S,T is trivial & createGraph {0 ,1},{0 },S,T is finite & createGraph {0 ,1},{0 },S,T is simple & createGraph {0 ,1},{0 },S,T is complete )
now assume
card (the_Vertices_of (createGraph {0 ,1},{0 },S,T)) = 1
;
:: thesis: contradictionthen consider x being
set such that A3:
the_Vertices_of (createGraph {0 ,1},{0 },S,T) = {x}
by CARD_2:60;
thus
contradiction
by A2, A3, ZFMISC_1:9;
:: thesis: verum end;
hence
( not createGraph {0 ,1},{0 },S,T is trivial & createGraph {0 ,1},{0 },S,T is finite )
by GLIB_000:def 21; :: thesis: ( createGraph {0 ,1},{0 },S,T is simple & createGraph {0 ,1},{0 },S,T is complete )
A4:
(the_Source_of (createGraph {0 ,1},{0 },S,T)) . 0 = 0
by A2, FUNCOP_1:87;
A5:
(the_Target_of (createGraph {0 ,1},{0 },S,T)) . 0 = 1
by A2, FUNCOP_1:87;
0 in the_Edges_of (createGraph {0 ,1},{0 },S,T)
by A2, TARSKI:def 1;
then A6:
0 Joins 0 ,1, createGraph {0 ,1},{0 },S,T
by A4, A5, GLIB_000:def 15;
now let v,
e be
set ;
:: thesis: not e Joins v,v, createGraph {0 ,1},{0 },S,Tassume A7:
e Joins v,
v,
createGraph {0 ,1},
{0 },
S,
T
;
:: thesis: contradictionreconsider v =
v as
Vertex of
(createGraph {0 ,1},{0 },S,T) by A7, GLIB_000:16;
e in the_Edges_of (createGraph {0 ,1},{0 },S,T)
by A7, GLIB_000:def 15;
then
e Joins 0 ,1,
createGraph {0 ,1},
{0 },
S,
T
by A2, A6, TARSKI:def 1;
then
( (
0 = v & 1
= v ) or (
0 = v & 1
= v ) )
by A7, GLIB_000:18;
hence
contradiction
;
:: thesis: verum end;
then A8:
createGraph {0 ,1},{0 },S,T is loopless
by GLIB_000:21;
now let e1,
e2,
v1,
v2 be
set ;
:: thesis: ( e1 Joins v1,v2, createGraph {0 ,1},{0 },S,T & e2 Joins v1,v2, createGraph {0 ,1},{0 },S,T implies not e1 <> e2 )assume A9:
(
e1 Joins v1,
v2,
createGraph {0 ,1},
{0 },
S,
T &
e2 Joins v1,
v2,
createGraph {0 ,1},
{0 },
S,
T )
;
:: thesis: not e1 <> e2assume A10:
e1 <> e2
;
:: thesis: contradiction
(
e1 in {0 } &
e2 in {0 } )
by A2, A9, GLIB_000:def 15;
then
(
e1 = 0 &
e2 = 0 )
by TARSKI:def 1;
hence
contradiction
by A10;
:: thesis: verum end;
then
createGraph {0 ,1},{0 },S,T is non-multi
by GLIB_000:def 22;
hence
createGraph {0 ,1},{0 },S,T is simple
by A8; :: thesis: createGraph {0 ,1},{0 },S,T is complete
now let u,
v be
Vertex of
(createGraph {0 ,1},{0 },S,T);
:: thesis: ( u <> v implies b1,b2 are_adjacent )assume A11:
u <> v
;
:: thesis: b1,b2 are_adjacent per cases
( u = 0 or u = 1 )
by A2, TARSKI:def 2;
suppose A12:
u = 0
;
:: thesis: b1,b2 are_adjacent then A13:
v = 1
by A2, A11, TARSKI:def 2;
0 in the_Edges_of (createGraph {0 ,1},{0 },S,T)
by A2, TARSKI:def 1;
then
0 Joins u,
v,
createGraph {0 ,1},
{0 },
S,
T
by A4, A5, A12, A13, GLIB_000:def 15;
hence
u,
v are_adjacent
by Def3;
:: thesis: verum end; suppose A14:
u = 1
;
:: thesis: b1,b2 are_adjacent then A15:
v = 0
by A2, A11, TARSKI:def 2;
0 in the_Edges_of (createGraph {0 ,1},{0 },S,T)
by A2, TARSKI:def 1;
then
0 Joins v,
u,
createGraph {0 ,1},
{0 },
S,
T
by A4, A5, A14, A15, GLIB_000:def 15;
hence
u,
v are_adjacent
by Def3;
:: thesis: verum end; end; end;
hence
createGraph {0 ,1},{0 },S,T is complete
by Def6; :: thesis: verum