"Source: Text/Incidence/Graph.text";
"Line: 297";
"Date: Fri Sep 26 12:10:10 2025";
"Main: Fri Sep 26 14:29:19 2025";
// original file: Text/Incidence/Graph.text, line: 297
// Example: H162E2 ()
print "Example: H162E2";
ei := GetEchoInput();
SetEchoInput(true);
P := Graph< 10 | { 1, 2 }, { 1, 5 }, { 1, 6 }, { 2, 3 }, { 2, 7 },
           { 3, 4 }, { 3, 8 }, { 4, 5 }, { 4, 9 }, { 5, 10 },
           { 6, 8 }, { 6, 9 }, { 7, 9 }, { 7, 10 }, { 8, 10 } >;
P := Graph< 10 | [ { 2, 5, 6 }, { 1, 3, 7 }, { 2, 4, 8 }, { 3, 5, 9 },
              { 1, 4, 10 }, { 1, 8, 9 }, { 2, 9, 10 }, { 3, 6, 10 },
              { 4, 6, 7 }, { 5, 7, 8 } ] >;
PS := Graph< 10 | [ { 2, 5, 6 }, { 1, 3, 7 }, { 2, 4, 8 }, { 3, 5, 9 },
              { 1, 4, 10 }, { 1, 8, 9 }, { 2, 9, 10 }, { 3, 6, 10 },
              { 4, 6, 7 }, { 5, 7, 8 } ] : SparseRep := true >;
assert PS eq P;
PS := Graph< 10 | P : SparseRep := true >;
assert PS eq P;
M := MatrixRing( Integers(), 10 );
P := Graph< 10 | M![ 0,1,0,0,1,1,0,0,0,0,
                  1,0,1,0,0,0,1,0,0,0,
                  0,1,0,1,0,0,0,1,0,0,
                  0,0,1,0,1,0,0,0,1,0,
                  1,0,0,1,0,0,0,0,0,1,
                  1,0,0,0,0,0,0,1,1,0,
                  0,1,0,0,0,0,0,0,1,1,
                  0,0,1,0,0,1,0,0,0,1,
                  0,0,0,1,0,1,1,0,0,0,
                  0,0,0,0,1,0,1,1,0,0] >;
P;
SetEchoInput(ei);
