Keyboard Row

CMakeLists.txt

@@ -249,6 +249,7 @@ add_task(jump-game-iii)
 add_task(jump-game-iv)
 add_task(k-closest-points-to-origin)
 add_task(k-radius-subarray-averages)
+add_task(keyboard-row)
 add_task(keys-and-rooms)
 add_task(kids-with-the-greatest-number-of-candies)
 add_task(knight-probability-in-chessboard)

solutions/keyboard-row/CMakeLists.txt

@@ -0,0 +1 @@
+add_catch(test_keyboard_row test.cpp)

solutions/keyboard-row/solution.hpp

@@ -0,0 +1,27 @@
+#pragma once
+
+#include <algorithm>
+#include <cctype>
+#include <set>
+#include <string>
+#include <vector>
+
+class Solution {
+public:
+  static std::vector<std::string>
+  findWords(const std::vector<std::string> &words) {
+    const std::vector<int> rows{2, 3, 3, 2, 1, 2, 2, 2, 1, 2, 2, 2, 3,
+                                3, 1, 1, 1, 1, 2, 1, 1, 3, 1, 3, 1, 3};
+    std::vector<std::string> ans;
+    for (const auto &word : words) {
+      std::set<int> set;
+      std::transform(
+          word.begin(), word.end(), std::inserter(set, set.begin()),
+          [&rows](unsigned char c) { return rows[std::tolower(c) - 'a']; });
+      if (set.size() == 1) {
+        ans.push_back(word);
+      }
+    }
+    return ans;
+  }
+};

solutions/keyboard-row/test.cpp

@@ -0,0 +1,30 @@
+#include <catch.hpp>
+
+#include <solution.hpp>
+
+TEST_CASE("Simple") {
+  struct TestCase {
+    std::vector<std::string> words;
+    std::vector<std::string> expected;
+  };
+
+  std::vector<TestCase> test_cases{
+      {
+          .words{"Hello", "Alaska", "Dad", "Peace"},
+          .expected{"Alaska", "Dad"},
+      },
+      {
+          .words{"omk"},
+          .expected{},
+      },
+      {
+          .words{"adsdf", "sfd"},
+          .expected{"adsdf", "sfd"},
+      },
+  };
+
+  for (const auto &[words, expected] : test_cases) {
+    const auto actual = Solution::findWords(words);
+    REQUIRE(expected == actual);
+  }
+}