Add practice exercise: word-search

config.json

@@ -626,6 +626,14 @@
         "prerequisites": [],
         "difficulty": 8
       },
+      {
+        "slug": "word-search",
+        "name": "Word Search",
+        "uuid": "3d82c7c8-0988-438b-b9db-345c9eb61250",
+        "practices": [],
+        "prerequisites": [],
+        "difficulty": 8
+      },
       {
         "slug": "wordy",
         "name": "Wordy",

exercises/practice/word-search/.docs/instructions.md

@@ -0,0 +1,24 @@
+# Instructions
+
+In word search puzzles you get a square of letters and have to find specific words in them.
+
+For example:
+
+```text
+jefblpepre
+camdcimgtc
+oivokprjsm
+pbwasqroua
+rixilelhrs
+wolcqlirpc
+screeaumgr
+alxhpburyi
+jalaycalmp
+clojurermt
+```
+
+There are several programming languages hidden in the above square.
+
+Words can be hidden in all kinds of directions: left-to-right, right-to-left, vertical and diagonal.
+
+Given a puzzle and a list of words return the location of the first and last letter of each word.

exercises/practice/word-search/.meta/config.json

@@ -0,0 +1,17 @@
+{
+  "authors": [
+    "jimmytty"
+  ],
+  "files": {
+    "solution": [
+      "word-search.sql"
+    ],
+    "test": [
+      "word-search_test.sql"
+    ],
+    "example": [
+      ".meta/example.sql"
+    ]
+  },
+  "blurb": "Create a program to solve a word search puzzle."
+}

exercises/practice/word-search/.meta/example.sql

@@ -0,0 +1,216 @@
+DROP TABLE IF EXISTS letters;
+CREATE TEMPORARY TABLE letters (
+  grid TEXT    NOT NULL,
+  chr  TEXT    NOT NULL,
+  row  INTEGER NOT NULL,
+  col  INTEGER NOT NULL
+);
+WITH
+  to_lines AS (
+    SELECT grid,
+           j.value AS line,
+           LENGTH(j.value) AS len,
+           j.key AS row
+      FROM (SELECT DISTINCT JSON_EXTRACT(input, '$.grid') AS grid
+              FROM "word-SEARCH"),
+           JSON_EACH(grid) j
+  ),
+  to_chars AS (
+    SELECT grid, SUBSTR(line, g.value, 1) AS chr, row, g.value - 1 col
+      FROM to_lines, GENERATE_SERIES(1, to_lines.len) g
+  )
+INSERT INTO letters
+      (grid, chr, row, col)
+SELECT grid, chr, row, col
+  FROM to_chars
+;
+
+DROP TABLE IF EXISTS strings;
+CREATE TEMPORARY TABLE strings (
+  grid   TEXT NOT NULL,
+  string TEXT NOT NULL,
+  array  TEXT NOT NULL
+);
+INSERT INTO strings (grid, string, array)
+SELECT grid,
+       GROUP_CONCAT(chr, ''),
+       JSON_GROUP_ARRAY(JSON_ARRAY(chr, JSON_ARRAY(row, col)))
+  FROM (
+    SELECT grid, chr, row, col
+      FROM letters
+     ORDER BY row ASC, col ASC
+  )
+ GROUP BY grid, row
+HAVING LENGTH(GROUP_CONCAT(chr, '')) > 1
+;
+INSERT INTO strings (grid, string, array)
+SELECT grid,
+       GROUP_CONCAT(chr, ''),
+       JSON_GROUP_ARRAY(JSON_ARRAY(chr, JSON_ARRAY(row, col)))
+  FROM (
+    SELECT grid, chr, row, col
+      FROM letters
+     ORDER BY row DESC, col DESC
+  )
+ GROUP BY grid, row
+HAVING LENGTH(GROUP_CONCAT(chr, '')) > 1
+;
+INSERT INTO strings (grid, string, array)
+SELECT grid,
+       GROUP_CONCAT(chr, ''),
+       JSON_GROUP_ARRAY(JSON_ARRAY(chr, JSON_ARRAY(row, col)))
+  FROM (
+    SELECT grid, chr, row, col
+      FROM letters
+     ORDER BY col ASC, row ASC
+  )
+ GROUP BY grid, col
+HAVING LENGTH(GROUP_CONCAT(chr, '')) > 1
+;
+INSERT INTO strings (grid, string, array)
+SELECT grid,
+       GROUP_CONCAT(chr, ''),
+       JSON_GROUP_ARRAY(JSON_ARRAY(chr, JSON_ARRAY(row, col)))
+  FROM (
+    SELECT grid, chr, row, col
+      FROM letters
+     ORDER BY col DESC, row DESC
+  )
+ GROUP BY grid, col
+HAVING LENGTH(GROUP_CONCAT(chr, '')) > 1
+;
+
+WITH
+  bounds (grid, mrow, mcol) AS (
+    SELECT grid, MAX(row), MAX(col)
+      FROM letters
+     GROUP BY grid
+  ),
+  starts AS (
+    SELECT grid,
+           gr.value row,
+           gc.value col
+      FROM bounds, GENERATE_SERIES(0, mrow) gr, GENERATE_SERIES(0, mcol) gc
+  ),
+  r2l_coords AS (
+    SELECT grid,
+           JSON_GROUP_ARRAY(JSON(coord)) AS coords
+      FROM (
+        SELECT DISTINCT
+          starts.grid,
+          row,
+          col,
+          JSON_ARRAY(row + g.value, col + g.value) coord
+          FROM bounds, starts, GENERATE_SERIES(0, mrow) g
+         WHERE bounds.grid = starts.grid
+           AND row + g.value <= mrow
+           AND col + g.value <= mcol
+      )
+     GROUP BY grid, row, col
+    HAVING JSON_ARRAY_LENGTH(coords) > 1
+  ),
+  l2r_coords AS (
+    SELECT grid,
+           JSON_GROUP_ARRAY(JSON(coord)) AS coords
+      FROM (
+        SELECT DISTINCT
+          starts.grid,
+          row,
+          col,
+          g.value,
+          JSON_ARRAY(row + g.value, col - g.value) coord
+          FROM bounds, starts, GENERATE_SERIES(0, mrow) g
+         WHERE bounds.grid = starts.grid
+           AND row + g.value <= mrow
+           AND col - g.value >= 0
+      )
+     GROUP BY grid, row, col
+    HAVING JSON_ARRAY_LENGTH(coords) > 1
+  ),
+  chrs AS (
+    SELECT letters.*,
+           JSON_ARRAY(letters.row, letters.col) AS row_col,
+           r2l_coords.coords
+      FROM letters, r2l_coords
+     WHERE letters.grid = r2l_coords.grid
+       AND row_col IN ((SELECT j.value FROM JSON_EACH(coords) j))
+     UNION ALL
+    SELECT letters.*,
+           JSON_ARRAY(letters.row, letters.col) AS row_col,
+           l2r_coords.coords
+      FROM letters, l2r_coords
+     WHERE letters.grid = l2r_coords.grid
+       AND row_col IN ((SELECT j.value FROM JSON_EACH(coords) j))
+  ),
+  straight AS (
+    SELECT grid,
+           GROUP_CONCAT(chr, '') AS string,
+           JSON_GROUP_ARRAY(JSON_ARRAY(chr, JSON_ARRAY(row, col))) array
+      FROM (SELECT * FROM chrs ORDER BY grid, row_col ASC)
+     GROUP BY grid, coords
+  ),
+  reversed AS (
+    SELECT grid,
+           GROUP_CONCAT(chr, '') AS string,
+           JSON_GROUP_ARRAY(JSON_ARRAY(chr, JSON_ARRAY(row, col))) array
+      FROM (SELECT * FROM chrs ORDER BY grid, row_col DESC)
+     GROUP BY grid, coords
+  )
+INSERT INTO strings (grid, string, array)
+SELECT * FROM straight
+ UNION ALL
+SELECT * FROM reversed
+;
+
+WITH
+  find AS (
+    SELECT input,
+           j.value AS word,
+           (SELECT
+              JSON_EXTRACT(
+                array,
+                PRINTF('$[%d][1]', INSTR(string, j.value) - 1),
+                PRINTF('$[%d][1]', INSTR(string, j.value) +
+                       LENGTH(j.value) - 2
+                )
+              )
+              FROM strings
+             WHERE JSON_EXTRACT(input, '$.grid') = grid
+               AND INSTR(string, j.value)
+           ) AS bounds
+      FROM "word-search",
+           JSON_EACH(JSON_EXTRACT(input, '$.wordsToSearchFor')) j
+  ),
+  results AS (
+    SELECT input,
+           JSON_GROUP_OBJECT(word, JSON(object)) result
+      FROM (
+        SELECT
+          input,
+          word,
+          IIF(
+            bounds ISNULL,
+            bounds,
+            JSON_OBJECT(
+              'start',
+              JSON_OBJECT(
+                'column', JSON_EXTRACT(bounds, '$[0][1]') + 1,
+                'row',    JSON_EXTRACT(bounds, '$[0][0]') + 1
+              ),
+              'end',
+              JSON_OBJECT(
+                'column', JSON_EXTRACT(bounds, '$[1][1]') + 1,
+                'row',    JSON_EXTRACT(bounds, '$[1][0]') + 1
+              )
+            )
+          ) object
+          FROM find
+         ORDER BY input, word
+      )
+     GROUP BY input
+  )
+UPDATE "word-search"
+   SET result = results.result
+  FROM results
+ WHERE "word-search".input = results.input
+;

exercises/practice/word-search/.meta/tests.toml

@@ -0,0 +1,82 @@
+# This is an auto-generated file.
+#
+# Regenerating this file via `configlet sync` will:
+# - Recreate every `description` key/value pair
+# - Recreate every `reimplements` key/value pair, where they exist in problem-specifications
+# - Remove any `include = true` key/value pair (an omitted `include` key implies inclusion)
+# - Preserve any other key/value pair
+#
+# As user-added comments (using the # character) will be removed when this file
+# is regenerated, comments can be added via a `comment` key.
+
+[b4057815-0d01-41f0-9119-6a91f54b2a0a]
+description = "Should accept an initial game grid and a target search word"
+
+[6b22bcc5-6cbf-4674-931b-d2edbff73132]
+description = "Should locate one word written left to right"
+
+[ff462410-434b-442d-9bc3-3360c75f34a8]
+description = "Should locate the same word written left to right in a different position"
+
+[a02febae-6347-443e-b99c-ab0afb0b8fca]
+description = "Should locate a different left to right word"
+
+[e42e9987-6304-4e13-8232-fa07d5280130]
+description = "Should locate that different left to right word in a different position"
+
+[9bff3cee-49b9-4775-bdfb-d55b43a70b2f]
+description = "Should locate a left to right word in two line grid"
+
+[851a35fb-f499-4ec1-9581-395a87903a22]
+description = "Should locate a left to right word in three line grid"
+
+[2f3dcf84-ba7d-4b75-8b8d-a3672b32c035]
+description = "Should locate a left to right word in ten line grid"
+
+[006d4856-f365-4e84-a18c-7d129ce9eefb]
+description = "Should locate that left to right word in a different position in a ten line grid"
+
+[eff7ac9f-ff11-443e-9747-40850c12ab60]
+description = "Should locate a different left to right word in a ten line grid"
+
+[dea39f86-8c67-4164-8884-13bfc48bd13b]
+description = "Should locate multiple words"
+
+[29e6a6a5-f80c-48a6-8e68-05bbbe187a09]
+description = "Should locate a single word written right to left"
+
+[3cf34428-b43f-48b6-b332-ea0b8836011d]
+description = "Should locate multiple words written in different horizontal directions"
+
+[2c8cd344-a02f-464b-93b6-8bf1bd890003]
+description = "Should locate words written top to bottom"
+
+[9ee1e43d-e59d-4c32-9a5f-6a22d4a1550f]
+description = "Should locate words written bottom to top"
+
+[6a21a676-f59e-4238-8e88-9f81015afae9]
+description = "Should locate words written top left to bottom right"
+
+[c9125189-1861-4b0d-a14e-ba5dab29ca7c]
+description = "Should locate words written bottom right to top left"
+
+[b19e2149-7fc5-41ec-a8a9-9bc6c6c38c40]
+description = "Should locate words written bottom left to top right"
+
+[69e1d994-a6d7-4e24-9b5a-db76751c2ef8]
+description = "Should locate words written top right to bottom left"
+
+[695531db-69eb-463f-8bad-8de3bf5ef198]
+description = "Should fail to locate a word that is not in the puzzle"
+
+[fda5b937-6774-4a52-8f89-f64ed833b175]
+description = "Should fail to locate words that are not on horizontal, vertical, or diagonal lines"
+
+[5b6198eb-2847-4e2f-8efe-65045df16bd3]
+description = "Should not concatenate different lines to find a horizontal word"
+
+[eba44139-a34f-4a92-98e1-bd5f259e5769]
+description = "Should not wrap around horizontally to find a word"
+
+[cd1f0fa8-76af-4167-b105-935f78364dac]
+description = "Should not wrap around vertically to find a word"

exercises/practice/word-search/create_fixture.sql

@@ -0,0 +1,10 @@
+DROP TABLE IF EXISTS "word-search";
+CREATE TABLE "word-search" (
+  input  TEXT NOT NULL,   -- json object
+  result TEXT             -- json object
+);
+
+.mode csv
+.import ./data.csv "word-search"
+
+UPDATE "word-search" SET result = NULL;