Uncommon Words from Two Sentences

CMakeLists.txt

@@ -819,6 +819,7 @@ add_task(two-sum-iv-input-is-a-bst)
 add_task(ugly-number)
 add_task(ugly-number-ii)
 add_task(ugly-number-iii)
+add_task(uncommon-words-from-two-sentences)
 add_task(uncrossed-lines)
 add_task(unique-binary-search-trees)
 add_task(unique-binary-search-trees-ii)

solutions/uncommon-words-from-two-sentences/CMakeLists.txt

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

solutions/uncommon-words-from-two-sentences/solution.hpp

@@ -0,0 +1,26 @@
+#pragma once
+
+#include <sstream>
+#include <string>
+#include <unordered_map>
+#include <vector>
+
+class Solution {
+public:
+  static std::vector<std::string> uncommonFromSentences(std::string s1,
+                                                        std::string s2) {
+    std::stringstream stream(s1 + " " + s2);
+    std::unordered_map<std::string, int> counter;
+    for (std::string word; stream >> word;) {
+      ++counter[word];
+    }
+
+    std::vector<std::string> uncommon;
+    for (const auto &[word, frequency] : counter) {
+      if (frequency == 1) {
+        uncommon.push_back(word);
+      }
+    }
+    return uncommon;
+  }
+};

solutions/uncommon-words-from-two-sentences/test.cpp

@@ -0,0 +1,31 @@
+#include <catch.hpp>
+
+#include <solution.hpp>
+
+TEST_CASE("Simple") {
+  struct TestCase {
+    std::string s1;
+    std::string s2;
+    std::vector<std::string> expected;
+  };
+
+  std::vector<TestCase> test_cases{
+      {
+          .s1 = "this apple is sweet",
+          .s2 = "this apple is sour",
+          .expected{"sweet", "sour"},
+      },
+      {
+          .s1 = "apple apple",
+          .s2 = "banana",
+          .expected{"banana"},
+      },
+  };
+
+  for (auto [s1, s2, expected] : test_cases) {
+    auto actual = Solution::uncommonFromSentences(s1, s2);
+    std::sort(actual.begin(), actual.end());
+    std::sort(expected.begin(), expected.end());
+    REQUIRE(expected == actual);
+  }
+}