Problem11 上下左右斜めの、連続する4つの数字の積

08 02 22 97 38 15 00 40 00 75 04 05 07 78 52 12 50 77 91 08
49 49 99 40 17 81 18 57 60 87 17 40 98 43 69 48 04 56 62 00
81 49 31 73 55 79 14 29 93 71 40 67 53 88 30 03 49 13 36 65
52 70 95 23 04 60 11 42 69 24 68 56 01 32 56 71 37 02 36 91
22 31 16 71 51 67 63 89 41 92 36 54 22 40 40 28 66 33 13 80
24 47 32 60 99 03 45 02 44 75 33 53 78 36 84 20 35 17 12 50
32 98 81 28 64 23 67 10 26 38 40 67 59 54 70 66 18 38 64 70
67 26 20 68 02 62 12 20 95 63 94 39 63 08 40 91 66 49 94 21
24 55 58 05 66 73 99 26 97 17 78 78 96 83 14 88 34 89 63 72
21 36 23 09 75 00 76 44 20 45 35 14 00 61 33 97 34 31 33 95
78 17 53 28 22 75 31 67 15 94 03 80 04 62 16 14 09 53 56 92
16 39 05 42 96 35 31 47 55 58 88 24 00 17 54 24 36 29 85 57
86 56 00 48 35 71 89 07 05 44 44 37 44 60 21 58 51 54 17 58
19 80 81 68 05 94 47 69 28 73 92 13 86 52 17 77 04 89 55 40
04 52 08 83 97 35 99 16 07 97 57 32 16 26 26 79 33 27 98 66
88 36 68 87 57 62 20 72 03 46 33 67 46 55 12 32 63 93 53 69
04 42 16 73 38 25 39 11 24 94 72 18 08 46 29 32 40 62 76 36
20 69 36 41 72 30 23 88 34 62 99 69 82 67 59 85 74 04 36 16
20 73 35 29 78 31 90 01 74 31 49 71 48 86 81 16 23 57 05 54
01 70 54 71 83 51 54 69 16 92 33 48 61 43 52 01 89 19 67 48

上の 20*20 の数字のなか、赤くマークされた数字の積は 26*63*78*14 = 1788696 となる。
上下左右斜めのいずれかの方向で連続する4つの数字の積のうち最大のものを求めよ。

SQL

declare
    type Yoko is VArray(20) of pls_Integer;
    type NumMapDef is VArray(20) of yoko;
    NumMap NumMapDef :=NumMapDef(yoko(08,02,22,97,38,15,00,40,00,75,04,05,07,78,52,12,50,77,91,08),
                                 yoko(49,49,99,40,17,81,18,57,60,87,17,40,98,43,69,48,04,56,62,00),
                                 yoko(81,49,31,73,55,79,14,29,93,71,40,67,53,88,30,03,49,13,36,65),
                                 yoko(52,70,95,23,04,60,11,42,69,24,68,56,01,32,56,71,37,02,36,91),
                                 yoko(22,31,16,71,51,67,63,89,41,92,36,54,22,40,40,28,66,33,13,80),
                                 yoko(24,47,32,60,99,03,45,02,44,75,33,53,78,36,84,20,35,17,12,50),
                                 yoko(32,98,81,28,64,23,67,10,26,38,40,67,59,54,70,66,18,38,64,70),
                                 yoko(67,26,20,68,02,62,12,20,95,63,94,39,63,08,40,91,66,49,94,21),
                                 yoko(24,55,58,05,66,73,99,26,97,17,78,78,96,83,14,88,34,89,63,72),
                                 yoko(21,36,23,09,75,00,76,44,20,45,35,14,00,61,33,97,34,31,33,95),
                                 yoko(78,17,53,28,22,75,31,67,15,94,03,80,04,62,16,14,09,53,56,92),
                                 yoko(16,39,05,42,96,35,31,47,55,58,88,24,00,17,54,24,36,29,85,57),
                                 yoko(86,56,00,48,35,71,89,07,05,44,44,37,44,60,21,58,51,54,17,58),
                                 yoko(19,80,81,68,05,94,47,69,28,73,92,13,86,52,17,77,04,89,55,40),
                                 yoko(04,52,08,83,97,35,99,16,07,97,57,32,16,26,26,79,33,27,98,66),
                                 yoko(88,36,68,87,57,62,20,72,03,46,33,67,46,55,12,32,63,93,53,69),
                                 yoko(04,42,16,73,38,25,39,11,24,94,72,18,08,46,29,32,40,62,76,36),
                                 yoko(20,69,36,41,72,30,23,88,34,62,99,69,82,67,59,85,74,04,36,16),
                                 yoko(20,73,35,29,78,31,90,01,74,31,49,71,48,86,81,16,23,57,05,54),
                                 yoko(01,70,54,71,83,51,54,69,16,92,33,48,61,43,52,01,89,19,67,48));
    MaxVal pls_Integer := 0;
    utiwake VarChar2(20);

    procedure UpdateMax(p1 pls_Integer,p2 pls_Integer,p3 pls_Integer,p4 pls_Integer) Is
        wk_Val pls_Integer;
    begin
        wk_Val := p1*p2*p3*p4;
        if MaxVal < wk_Val then
            MaxVal := wk_Val;
            utiwake := to_char(p1) || '*' || to_char(p2) || '*' || to_char(p3) || '*' || to_char(p4);
        end if;
    end;
begin
    for Y in 1..20-3 Loop
        for X in 1..20-3 Loop
            UpdateMax(NumMap(X)(Y),NumMap(X+1)(Y),NumMap(X+2)(Y),NumMap(X+3)(Y));
            UpdateMax(NumMap(X)(Y),NumMap(X)(Y+1),NumMap(X)(Y+2),NumMap(X)(Y+3));
            UpdateMax(NumMap(X)(Y),NumMap(X+1)(Y+1),NumMap(X+2)(Y+2),NumMap(X+3)(Y+3));
        end Loop;
    end Loop;
    DBMS_Output.Put_Line(utiwake || '=' || to_char(MaxVal));
end;
/

実行結果

66*91*88*97=51267216

解説

固定長配列であるVArray型を使用してます。

C#での解