都道府県コード(PrefCode)に則り隣接県を示した配列。
地続き

$AdjacentPrefectures = [
    1 => [],
    2 => [3, 5,],
    3 => [2, 4, 5,],
    4 => [3, 5, 6, 7,],
    5 => [2, 3, 4, 6,],
    6 => [4, 5, 7, 15,],
    7 => [4, 6, 8, 9, 10, 15,],
    8 => [7, 9, 11, 12,],
    9 => [7, 8, 10, 11,],
    10 => [7, 9, 11, 15, 20,],
    11 => [8, 9, 10, 12, 13, 19, 20],
    12 => [8, 11, 13,],
    13 => [11, 12, 14, 19],
    14 => [13, 19, 22],
    15 => [6, 7, 10, 16, 20,],
    16 => [15, 17, 20, 21],
    17 => [16, 18, 21,],
    18 => [17, 21, 25, 26],
    19 => [11, 13, 14, 20, 22,],
    20 => [10, 11, 15, 16, 19, 21, 22, 23,],
    21 => [16, 17, 18, 20, 23, 24, 25,],
    22 => [14, 19, 20, 23,],
    23 => [20, 21, 22, 24,],
    24 => [21, 23, 25, 26, 29, 30,],
    25 => [18, 21, 24, 26,],
    26 => [18, 24, 25, 27, 28, 29,],
    27 => [26, 28, 29, 30,],
    28 => [26, 27, 31, 33,],
    29 => [24, 26, 27, 30,],
    30 => [24, 27, 29,],
    31 => [28, 32, 33, 34,],
    32 => [31, 34, 35,],
    33 => [28, 31, 34,],
    34 => [31, 32, 33, 35,],
    35 => [32, 34,],
    36 => [37, 38, 39,],
    37 => [36, 38,],
    38 => [36, 37, 39,],
    39 => [36, 38,],
    40 => [41, 43, 44,],
    41 => [40, 42],
    42 => [41,],
    43 => [40, 44, 45, 46,],
    44 => [40, 43, 45,],
    45 => [43, 44, 46, ],
    46 => [43, 45, ],
    47 => [],
];