ONLY DO WHAT ONLY YOU CAN DO

こけたら立ちなはれ 立ったら歩きなはれ

Scala で Project Euler Problem 11

まづ、格子状の文字列を List に 格納する

scala> var str = """
     | 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
     | """
str: java.lang.String =
"
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...
scala> str = str.replaceAll("\n", " ")
str: java.lang.String =  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 5...
scala> var lst = str.split(" ").toList
lst: List[java.lang.String] = List("", 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...
scala> var lst = str.trim().split(" ").toList
lst: List[java.lang.String] = List(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...

文字列の List を List の List ( 20×20 ) に 格納する

scala> for (i <- 0 to 19 ) yield {
     |     for (j <- 0 to 19 ) yield {
     |         lst(i * 20 + j)
     |     }
     | }
res19: scala.collection.immutable.IndexedSeq[scala.collection.immutable.IndexedSeq[java.lang.String]] = Vector(Vector(08, 02, 22, 97, 38, 15, 00, 40, 00, 75, 04, 05, 07, 78, 52, 12, 50, 77, 91, 08), Vector(49, 49, 99, 40, 17, 81, 18, 57, 60, 87, 17, 40, 98, 43, 69, 48, 04, 56, 62, 00), Vector(81, 49, 31, 73, 55, 79, 14, 29, 93, 71, 40, 67, 53, 88, 30, 03, 49, 13, 36, 65), Vector(52, 70, 95, 23, 04, 60, 11, 42, 69, 24, 68, 56, 01, 32, 56, 71, 37, 02, 36, 91), Vector(22, 31, 16, 71, 51, 67, 63, 89, 41, 92, 36, 54, 22, 40, 40, 28, 66, 33, 13, 80), Vector(24, 47, 32, 60, 99, 03, 45, 02, 44, 75, 33, 53, 78, 36, 84, 20, 35, 17, 12, 50), Vector(32, 98, 81, 28, 64, 23, 67, 10, 26, 38, 40, 67, 59, 54, 70, 66, 18, 38, 64, 70), Vector(67, 26, 20, 68, 02, 62, 12, 20, 95, 63, 94, 39, 63, 08, 40, 91,...
scala> var ls3 =
     | for (i <- 0 to 19 ) yield {
     |     for (j <- 0 to 19 ) yield {
     |         lst(i * 20 + j)
     |     }
     | }
ls3: scala.collection.immutable.IndexedSeq[scala.collection.immutable.IndexedSeq[java.lang.String]] = Vector(Vector(08, 02, 22, 97, 38, 15, 00, 40, 00, 75, 04, 05, 07, 78, 52, 12, 50, 77, 91, 08), Vector(49, 49, 99, 40, 17, 81, 18, 57, 60, 87, 17, 40, 98, 43, 69, 48, 04, 56, 62, 00), Vector(81, 49, 31, 73, 55, 79, 14, 29, 93, 71, 40, 67, 53, 88, 30, 03, 49, 13, 36, 65), Vector(52, 70, 95, 23, 04, 60, 11, 42, 69, 24, 68, 56, 01, 32, 56, 71, 37, 02, 36, 91), Vector(22, 31, 16, 71, 51, 67, 63, 89, 41, 92, 36, 54, 22, 40, 40, 28, 66, 33, 13, 80), Vector(24, 47, 32, 60, 99, 03, 45, 02, 44, 75, 33, 53, 78, 36, 84, 20, 35, 17, 12, 50), Vector(32, 98, 81, 28, 64, 23, 67, 10, 26, 38, 40, 67, 59, 54, 70, 66, 18, 38, 64, 70), Vector(67, 26, 20, 68, 02, 62, 12, 20, 95, 63, 94, 39, 63, 08, 40, 91, 6...
scala> var ls3 =
     | for (i <- 0 to 19 ) yield {
     |     for (j <- 0 to 19 ) yield {
     |         lst(i * 20 + j)
     |     }.toList
     | }.toList
ls3: scala.collection.immutable.IndexedSeq[List[List[Char]]] = Vector(List(List(0, 8), List(0, 2), List(2, 2), List(9, 7), List(3, 8), List(1, 5), List(0, 0), List(4, 0), List(0, 0), List(7, 5), List(0, 4), List(0, 5), List(0, 7), List(7, 8), List(5, 2), List(1, 2), List(5, 0), List(7, 7), List(9, 1), List(0, 8)), List(List(4, 9), List(4, 9), List(9, 9), List(4, 0), List(1, 7), List(8, 1), List(1, 8), List(5, 7), List(6, 0), List(8, 7), List(1, 7), List(4, 0), List(9, 8), List(4, 3), List(6, 9), List(4, 8), List(0, 4), List(5, 6), List(6, 2), List(0, 0)), List(List(8, 1), List(4, 9), List(3, 1), List(7, 3), List(5, 5), List(7, 9), List(1, 4), List(2, 9), List(9, 3), List(7, 1), List(4, 0), List(6, 7), List(5, 3), List(8, 8), List(3, 0), List(0, 3), List(4, 9), List(1, 3), List(3, 6), Li...
scala> var ls3 =
     | for (i <- 0 to 19 ) yield {
     |     for (j <- 0 to 19 ) yield {
     |         lst(i * 20 + j)
     |     }
     | }.toList.toList
ls3: scala.collection.immutable.IndexedSeq[List[java.lang.String]] = Vector(List(08, 02, 22, 97, 38, 15, 00, 40, 00, 75, 04, 05, 07, 78, 52, 12, 50, 77, 91, 08), List(49, 49, 99, 40, 17, 81, 18, 57, 60, 87, 17, 40, 98, 43, 69, 48, 04, 56, 62, 00), List(81, 49, 31, 73, 55, 79, 14, 29, 93, 71, 40, 67, 53, 88, 30, 03, 49, 13, 36, 65), List(52, 70, 95, 23, 04, 60, 11, 42, 69, 24, 68, 56, 01, 32, 56, 71, 37, 02, 36, 91), List(22, 31, 16, 71, 51, 67, 63, 89, 41, 92, 36, 54, 22, 40, 40, 28, 66, 33, 13, 80), List(24, 47, 32, 60, 99, 03, 45, 02, 44, 75, 33, 53, 78, 36, 84, 20, 35, 17, 12, 50), List(32, 98, 81, 28, 64, 23, 67, 10, 26, 38, 40, 67, 59, 54, 70, 66, 18, 38, 64, 70), List(67, 26, 20, 68, 02, 62, 12, 20, 95, 63, 94, 39, 63, 08, 40, 91, 66, 49, 94, 21), List(24, 55, 58, 05, 66, 73, 99, ...
scala> var ls3 = (
     | for (i <- 0 to 19 ) yield {
     |     for (j <- 0 to 19 ) yield {
     |         lst(i * 20 + j)
     |     }
     | }.toList).toList
ls3: List[List[java.lang.String]] = List(List(08, 02, 22, 97, 38, 15, 00, 40, 00, 75, 04, 05, 07, 78, 52, 12, 50, 77, 91, 08), List(49, 49, 99, 40, 17, 81, 18, 57, 60, 87, 17, 40, 98, 43, 69, 48, 04, 56, 62, 00), List(81, 49, 31, 73, 55, 79, 14, 29, 93, 71, 40, 67, 53, 88, 30, 03, 49, 13, 36, 65), List(52, 70, 95, 23, 04, 60, 11, 42, 69, 24, 68, 56, 01, 32, 56, 71, 37, 02, 36, 91), List(22, 31, 16, 71, 51, 67, 63, 89, 41, 92, 36, 54, 22, 40, 40, 28, 66, 33, 13, 80), List(24, 47, 32, 60, 99, 03, 45, 02, 44, 75, 33, 53, 78, 36, 84, 20, 35, 17, 12, 50), List(32, 98, 81, 28, 64, 23, 67, 10, 26, 38, 40, 67, 59, 54, 70, 66, 18, 38, 64, 70), List(67, 26, 20, 68, 02, 62, 12, 20, 95, 63, 94, 39, 63, 08, 40, 91, 66, 49, 94, 21), List(24, 55, 58, 05, 66, 73, 99, 26, 97, 17, 78, 78, 96, 83, 14, 88,...

隣り合った4つの数字を1組にして、List に 格納する

scala> var ls4:List[List[Int]] = Nil
ls4: List[List[Int]] = List()

scala> for (y <- 0 to 19) {
     |     for (x <- 0 to 16) {
     |         val ls:List[Int] =
     |         (for (i <- 0 to 3) yield {
     |             ls3(y)(x + i).toInt
     |         }).toList
     |         ls4 = ls::ls4
     |     }
     | }

scala> ls4
res37: List[List[Int]] = List(List(89, 19, 67, 48), List(1, 89, 19, 67), List(52, 1, 89, 19), List(43, 52, 1, 89), List(61, 43, 52, 1), List(48, 61, 43, 52), List(33, 48, 61, 43), List(92, 33, 48, 61), List(16, 92, 33, 48), List(69, 16, 92, 33), List(54, 69, 16, 92), List(51, 54, 69, 16), List(83, 51, 54, 69), List(71, 83, 51, 54), List(54, 71, 83, 51), List(70, 54, 71, 83), List(1, 70, 54, 71), List(23, 57, 5, 54), List(16, 23, 57, 5), List(81, 16, 23, 57), List(86, 81, 16, 23), List(48, 86, 81, 16), List(71, 48, 86, 81), List(49, 71, 48, 86), List(31, 49, 71, 48), List(74, 31, 49, 71), List(1, 74, 31, 49), List(90, 1, 74, 31), List(31, 90, 1, 74), List(78, 31, 90, 1), List(29, 78, 31, 90), List(35, 29, 78, 31), List(73, 35, 29, 78), List(20, 73, 35, 29), List(74, 4, 36, 16), List(85, ...

隣り合った4つの数字の積を、List に 格納する (右隣)

scala> var ls4:List[Int] = Nil
ls4: List[Int] = List()

scala> for (y <- 0 to 19) {
     |     for (x <- 0 to 16) {
     |         val ls:List[Int] =
     |         (for (i <- 0 to 3) yield {
     |             ls3(y)(x + i).toInt
     |         }).toList
     |         ls4 = ls.product::ls4
     |     }
     | }

scala> ls4
res39: List[Int] = List(5438256, 113297, 87932, 199004, 136396, 6547008, 4154832, 8889408, 2331648, 3351744, 5484672, 3040416, 15772158, 16229322, 16229322, 22275540, 268380, 353970, 104880, 1699056, 2563488, 5349888, 23740128, 14361312, 5176752, 7980826, 112406, 206460, 206460, 217620, 6310980, 2454270, 5779410, 1481900, 170496, 905760, 1484440, 24864370, 27552410, 22366074, 37529514, 34728804, 14399748, 18364896, 4266592, 2064480, 4371840, 2036880, 3188160, 7332768, 2036880, 6785280, 6031360, 2301440, 1707520, 341504, 192096, 476928, 974592, 2923776, 1786752, 967824, 257400, 407550, 2704650, 1109600, 1864128, 196224, 21426363, 9936864, 2249856, 1330560, 971520, 2034120, 5593830, 4678476, 305118, 327888, 198720, 267840, 5088960, 6149160, 20907144, 12139632, 18741888, 5762988, 6898122, ...

scala> ls4.max
res40: Int = 48477312

scala> for (y <- 0 to 16) {
     |     for (x <- 0 to 19) {
     |         val ls:List[Int] =
     |         (for (i <- 0 to 3) yield {
     |             ls3(y + i)(x).toInt
     |         }).toList
     |         ls4 = ls.product::ls4
     |     }
     | }

scala> ls4.max
res42: Int = 51267216

右下

scala> for (y <- 0 to 16) {
     |     for (x <- 0 to 16) {
     |         val ls:List[Int] =
     |         (for (i <- 0 to 3) yield {
     |             ls3(y + i)(x + i).toInt
     |         }).toList
     |         ls4 = ls.product::ls4
     |     }
     | }

scala> ls4.max
res44: Int = 51267216

左下

scala> for (y <- 0 to 16) {
     |     for (x <- 3 to 19) {
     |         val ls:List[Int] =
     |         (for (i <- 0 to 3) yield {
     |             ls3(y + i)(x - i).toInt
     |         }).toList
     |         ls4 = ls.product::ls4
     |     }
     | }

scala> ls4.max
res48: Int = 70600674

まとめ

scala> var str = """
     | 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
     | """
str: java.lang.String =
"
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...
scala> str = str.replaceAll("\n", " ")
str: java.lang.String =  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 5...
scala> var ls1 = str.trim().split(" ").toList
ls1: List[java.lang.String] = List(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...
scala> var ls3 = (
     | for (i <- 0 to 19 ) yield {
     |     for (j <- 0 to 19 ) yield {
     |         ls1(i * 20 + j)
     |     }
     | }.toList).toList
ls3: List[List[java.lang.String]] = List(List(08, 02, 22, 97, 38, 15, 00, 40, 00, 75, 04, 05, 07, 78, 52, 12, 50, 77, 91, 08), List(49, 49, 99, 40, 17, 81, 18, 57, 60, 87, 17, 40, 98, 43, 69, 48, 04, 56, 62, 00), List(81, 49, 31, 73, 55, 79, 14, 29, 93, 71, 40, 67, 53, 88, 30, 03, 49, 13, 36, 65), List(52, 70, 95, 23, 04, 60, 11, 42, 69, 24, 68, 56, 01, 32, 56, 71, 37, 02, 36, 91), List(22, 31, 16, 71, 51, 67, 63, 89, 41, 92, 36, 54, 22, 40, 40, 28, 66, 33, 13, 80), List(24, 47, 32, 60, 99, 03, 45, 02, 44, 75, 33, 53, 78, 36, 84, 20, 35, 17, 12, 50), List(32, 98, 81, 28, 64, 23, 67, 10, 26, 38, 40, 67, 59, 54, 70, 66, 18, 38, 64, 70), List(67, 26, 20, 68, 02, 62, 12, 20, 95, 63, 94, 39, 63, 08, 40, 91, 66, 49, 94, 21), List(24, 55, 58, 05, 66, 73, 99, 26, 97, 17, 78, 78, 96, 83, 14, 88,...
scala> var ls4:List[Int] = Nil
ls4: List[Int] = List()
scala> for (y <- 0 to 19; x <- 0 to 16) {
     |     ls4 = (for (i <- 0 to 3) yield {ls3(y)(x + i).toInt}).toList.product::ls4
     | }

scala> for (y <- 0 to 16; x <- 0 to 19) {
     |     ls4 = (for (i <- 0 to 3) yield {ls3(y + i)(x).toInt}).toList.product::ls4
     | }

scala> for (y <- 0 to 16; x <- 0 to 16) {
     |     ls4 = (for (i <- 0 to 3) yield {ls3(y + i)(x + i).toInt}).toList.product::ls4
     | }

scala> for (y <- 0 to 16; x <- 3 to 19) {
     |     ls4 = (for (i <- 0 to 3) yield {ls3(y + i)(x - i).toInt}).toList.product::ls4
     | }

scala> ls4.max
res7: Int = 70600674