Adjacency matrices show the number of direct links between vertices in a network. The topmost row and the leftmost column consist of the vertex labels, and the number in the corresponding cell indicates the number of direct links between the vertices. If A is directly linked to B then B is directly linked to A, so the adjacency matrix is symmetrical about the diagonal from upper left to bottom right.

A | B | C | D | E | F | |

A | 0 | 1 | 0 | 2 | 0 | 0 |

B | 1 | 0 | 1 | 0 | 0 | 0 |

C | 0 | 1 | 0 | 1 | 0 | 1 |

D | 2 | 0 | 1 | 0 | 1 | 1 |

E | 0 | 0 | 0 | 1 | 1 | 1 |

F | 0 | 0 | 1 | 1 | 1 | 0 |