From 5b25c7b0370700b56df1af3163afe39dbaefcaa5 Mon Sep 17 00:00:00 2001 From: VicRen Date: Sat, 10 Oct 2020 14:26:29 +0800 Subject: [PATCH] largest product in a grid --- largest_product_in_grid/digits.txt | 20 + .../largest_product_test.go | 356 ++++++++++++++++++ largest_product_in_grid/main.go | 187 +++++++++ 3 files changed, 563 insertions(+) create mode 100644 largest_product_in_grid/digits.txt create mode 100644 largest_product_in_grid/largest_product_test.go create mode 100644 largest_product_in_grid/main.go diff --git a/largest_product_in_grid/digits.txt b/largest_product_in_grid/digits.txt new file mode 100644 index 0000000..1fc75c6 --- /dev/null +++ b/largest_product_in_grid/digits.txt @@ -0,0 +1,20 @@ +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 \ No newline at end of file diff --git a/largest_product_in_grid/largest_product_test.go b/largest_product_in_grid/largest_product_test.go new file mode 100644 index 0000000..aa4e598 --- /dev/null +++ b/largest_product_in_grid/largest_product_test.go @@ -0,0 +1,356 @@ +package main + +import ( + "reflect" + "testing" +) + +func TestGetAdjacent(t *testing.T) { + tt := []struct { + name string + input [][]int + x int + y int + want int + }{ + { + "out_of_range", + [][]int{ + {1, 2}, + {1, 2}, + }, + 0, + 3, + 0, + }, + { + "out_of_range_2", + [][]int{ + {1, 2}, + {1, 2}, + }, + -1, + 1, + 0, + }, + { + "get_2", + [][]int{ + {1, 2}, + {1, 2}, + }, + 1, + 1, + 2, + }, + { + "get_1", + [][]int{ + {1, 2}, + {1, 2}, + }, + 0, + 0, + 1, + }, + } + + for _, tc := range tt { + t.Run(tc.name, func(t *testing.T) { + got := GetAdjacent(tc.input, tc.x, tc.y) + if got != tc.want { + t.Errorf("GetAdjacent(%v, %d, %d)=%d, want %d", tc.input, tc.x, tc.y, got, tc.want) + } + }) + } +} + +func TestGetRight4(t *testing.T) { + tt := []struct { + name string + input [][]int + want [][]int + }{ + { + "not_enough_digits", + [][]int{ + {1, 2, 3}, + {1, 2, 3}, + }, + nil, + }, + { + "exact_four", + [][]int{ + {1, 2, 3, 4}, + {1, 2, 3, 4}, + }, + [][]int{ + {1, 2, 3, 4}, + {1, 2, 3, 4}, + }, + }, + { + "more_than_four_1", + [][]int{ + {1, 2, 3, 4, 5}, + }, + [][]int{ + {1, 2, 3, 4}, + {2, 3, 4, 5}, + }, + }, + { + "more_than_four_2", + [][]int{ + {1, 2, 3, 4, 5}, + {1, 2, 3, 4, 5}, + }, + [][]int{ + {1, 2, 3, 4}, + {2, 3, 4, 5}, + {1, 2, 3, 4}, + {2, 3, 4, 5}, + }, + }, + { + "more_than_four_3", + [][]int{ + {1, 2, 3, 4, 5, 6}, + }, + [][]int{ + {1, 2, 3, 4}, + {2, 3, 4, 5}, + {3, 4, 5, 6}, + }, + }, + { + "more_than_four_4", + [][]int{ + {1, 2, 3, 4, 5, 6}, + {1, 2, 3, 4, 5, 6}, + }, + [][]int{ + {1, 2, 3, 4}, + {2, 3, 4, 5}, + {3, 4, 5, 6}, + {1, 2, 3, 4}, + {2, 3, 4, 5}, + {3, 4, 5, 6}, + }, + }, + } + + for _, tc := range tt { + t.Run(tc.name, func(t *testing.T) { + got := GetRight4(tc.input) + if !reflect.DeepEqual(got, tc.want) { + t.Errorf("GetRight4(%v)=%v, want %v", tc.input, got, tc.want) + } + }) + } +} + +func TestGetDown4(t *testing.T) { + tt := []struct { + name string + input [][]int + want [][]int + }{ + { + "not_enough_lines", + [][]int{ + {1, 2, 3}, + {1, 2, 3}, + }, + nil, + }, + { + "one_digits", + [][]int{ + {1}, + {1}, + {1}, + {1}, + }, + [][]int{{1, 1, 1, 1}}, + }, + { + "one_digits_2", + [][]int{ + {1, 2}, + {1}, + {1, 3}, + {1}, + }, + [][]int{{1, 1, 1, 1}}, + }, + { + "more_than_one_digits", + [][]int{ + {1, 2}, + {1, 3}, + {1, 3}, + {1, 5}, + }, + [][]int{ + {1, 1, 1, 1}, + {2, 3, 3, 5}, + }, + }, + { + "more_than_one_digits_2", + [][]int{ + {1, 2, 3}, + {1, 3, 4}, + {1, 3}, + {1, 5}, + }, + [][]int{ + {1, 1, 1, 1}, + {2, 3, 3, 5}, + }, + }, + { + "more_than_one_digits_3", + [][]int{ + {1, 2, 3}, + {1, 3, 4}, + {1, 3, 5}, + {1, 5, 10}, + }, + [][]int{ + {1, 1, 1, 1}, + {2, 3, 3, 5}, + {3, 4, 5, 10}, + }, + }, + { + "more_than_one_digits_4", + [][]int{ + {1, 2}, + {1}, + {1, 3}, + {1}, + {2}, + }, + [][]int{ + {1, 1, 1, 1}, + {1, 1, 1, 2}, + }, + }, + { + "more_than_one_digits_5", + [][]int{ + {1, 2}, + {1, 1}, + {1, 3}, + {1, 4}, + {2, 5}, + }, + [][]int{ + {1, 1, 1, 1}, + {1, 1, 1, 2}, + {2, 1, 3, 4}, + {1, 3, 4, 5}, + }, + }, + } + + for _, tc := range tt { + t.Run(tc.name, func(t *testing.T) { + got := GetDown4(tc.input) + if !reflect.DeepEqual(got, tc.want) { + t.Errorf("GetDown4(%v)=%v, want %v", tc.input, got, tc.want) + } + }) + } +} + +func TestGetDiagonal4(t *testing.T) { + tt := []struct { + name string + input [][]int + want [][]int + }{ + { + "not_enough_lines", + [][]int{ + {1, 2, 3}, + {1, 2, 3}, + }, + nil, + }, + { + "not_enough_columns", + [][]int{ + {1, 2, 3}, + {1, 2, 3}, + {1, 2, 3}, + {1, 2, 3}, + }, + nil, + }, + { + "one_result", + [][]int{ + {1, 2, 3}, + {1, 2, 3}, + {1, 2, 3}, + {1, 2, 3, 4}, + }, + [][]int{{1, 2, 3, 4}}, + }, + { + "more_than_one_result", + [][]int{ + {1, 2, 3}, + {1, 2, 3}, + {1, 2, 3, 4}, + {1, 2, 3, 4, 5}, + }, + [][]int{ + {1, 2, 3, 4}, + {2, 3, 4, 5}, + }, + }, + { + "more_than_one_result_2", + [][]int{ + {1, 2, 3}, + {1, 2, 3}, + {1, 2, 3, 4}, + {1, 2, 3, 4}, + {1, 2, 3, 4}, + }, + [][]int{ + {1, 2, 3, 4}, + {1, 2, 3, 4}, + }, + }, + { + "more_than_one_result_3", + [][]int{ + {1, 2, 3}, + {1, 2, 3}, + {1, 2, 3, 4}, + {1, 2, 3, 4, 5}, + {1, 2, 3, 4}, + }, + [][]int{ + {1, 2, 3, 4}, + {1, 2, 3, 4}, + {2, 3, 4, 5}, + }, + }, + } + + for _, tc := range tt { + t.Run(tc.name, func(t *testing.T) { + got := GetDiagonal4(tc.input) + if !reflect.DeepEqual(got, tc.want) { + t.Errorf("GetDiagonal4(%v)=%v, want %v", tc.input, got, tc.want) + } + }) + } +} diff --git a/largest_product_in_grid/main.go b/largest_product_in_grid/main.go new file mode 100644 index 0000000..0193b08 --- /dev/null +++ b/largest_product_in_grid/main.go @@ -0,0 +1,187 @@ +package main + +import ( + "bufio" + "fmt" + "io" + "os" + "strconv" + "strings" +) + +func main() { + fi, err := os.Open("./digits.txt") + if err != nil { + panic(err) + } + defer fi.Close() + + br := bufio.NewReader(fi) + var input [][]int + for { + a, _, e := br.ReadLine() + if e == io.EOF { + break + } + got := strings.Split(string(a), " ") + var line []int + for _, v := range got { + n, err := strconv.Atoi(v) + if err != nil { + panic(err) + } + line = append(line, n) + } + input = append(input, line) + } + fmt.Println("input=", input) + + d4 := GetDown4(input) + fmt.Println(d4) + + var product *Result + for y := 0; y < len(input); y++ { + for x := 0; x < len(input); x++ { + p1 := NewResult() + p2 := NewResult() + p3 := NewResult() + p4 := NewResult() + for i := 0; i < 4; i++ { + p1.Product *= GetAdjacent(input, y, x+i) + p1.Line = append(p1.Line, GetAdjacent(input, y, x+i)) + p2.Product *= GetAdjacent(input, y+i, x) + p2.Line = append(p2.Line, GetAdjacent(input, y+i, x)) + p3.Product *= GetAdjacent(input, y+i, x+i) + p3.Line = append(p3.Line, GetAdjacent(input, y+i, x+i)) + p4.Product *= GetAdjacent(input, y+i, x-i) + p4.Line = append(p4.Line, GetAdjacent(input, y+i, x-i)) + } + product = Max(p1, p2, p3, p4, product) + } + } + + fmt.Println("product is", product) +} + +type Result struct { + Product int + Line []int +} + +func NewResult() *Result { + return &Result{ + Product: 1, + } +} + +func (r *Result) String() string { + return fmt.Sprintln("product is", r.Product, "line:", r.Line) +} + +func Max(n, n2, n3, n4, n5 *Result) *Result { + max := NewResult() + if n.Product > max.Product { + max = n + } + if n2.Product > max.Product { + max = n2 + } + if n3.Product > max.Product { + max = n3 + } + if n4.Product > max.Product { + max = n4 + } + if n5 != nil && n5.Product > max.Product { + max = n5 + } + return max +} + +func GetAdjacent(input [][]int, x, y int) int { + if 0 <= y && y < len(input) && 0 <= x && x < len(input[y]) { + return input[y][x] + } + return 0 +} + +func GetRight4(input [][]int) [][]int { + var ret [][]int + for _, line := range input { + l := len(line) + if l < 4 { + continue + } else if l == 4 { + ret = append(ret, line) + } else { + for x := 0; x+4 <= l; x++ { + ret = append(ret, line[x:x+4]) + } + } + } + return ret +} + +func GetDown4(input [][]int) [][]int { + length := len(input) + if length < 4 { + return nil + } + maxL := 0 + for _, line := range input { + if len(line) > maxL { + maxL = len(line) + } + } + var ret [][]int + for c := 0; c < maxL; c++ { + for l := 0; l <= length-4; l++ { + var one []int + for d := 0; d < 4; d++ { + if len(input[l+d]) > c { + one = append(one, input[l+d][c]) + } + } + if len(one) == 4 { + ret = append(ret, one) + } + } + } + return ret +} + +func GetDiagonal4(input [][]int) [][]int { + l := len(input) + if l < 4 { + return nil + } + maxL := 0 + for _, line := range input { + if len(line) > maxL { + maxL = len(line) + } + } + if maxL < 4 { + return nil + } + var ret [][]int + for x := 0; x < maxL; x++ { + for y := 0; y < l; y++ { + if l < y+4 { + break + } + var l []int + for d := 0; d < 4; d++ { + line := input[d+y] + if len(line) <= d+x { + break + } + l = append(l, line[x+d]) + } + if len(l) == 4 { + ret = append(ret, l) + } + } + } + return ret +}