Solved contains-duplicate.

.vscode/tasks.json

@@ -9,7 +9,8 @@
                 "-g",
                 "${file}",
                 "-o",
-                "${fileDirname}/${fileBasenameNoExtension}"
+                "${fileDirname}/${fileBasenameNoExtension}",
+                "-Wall"
             ],
             "options": {
                 "cwd": "${fileDirname}"

CMakeLists.txt

@@ -24,4 +24,5 @@ include(GoogleTest)
 
 add_subdirectory( two-sum )
 add_subdirectory( longest-substring-without-repeating-characters )
-add_subdirectory( roman-numerals )
+add_subdirectory( roman-numerals )
+add_subdirectory( contains-duplicate )

contains-duplicate/CMakeLists.txt

@@ -0,0 +1,25 @@
+cmake_minimum_required(VERSION 3.14)
+project(contains_duplicate)
+
+# GoogleTest requires at least C++14
+set(CMAKE_CXX_STANDARD 14)
+set(CMAKE_CXX_STANDARD_REQUIRED ON)
+
+enable_testing()
+
+add_executable(
+  contains_duplicate_runner
+  runner.cpp
+)
+
+add_executable(
+  contains_duplicate_tests
+  tests.cpp
+)
+target_link_libraries(
+  contains_duplicate_tests
+  GTest::gtest_main
+)
+include_directories(${gtest_SOURCE_DIR}/include ${COMMON_INCLUDES})
+
+gtest_discover_tests(contains_duplicate_tests)

contains-duplicate/runner.cpp

@@ -0,0 +1,30 @@
+#include <iostream>
+#include <vector>
+
+#include "solution.hpp"
+
+std::ostream& operator<<(std::ostream& os, const std::vector<int>& vector) 
+{
+    os << "[";
+    bool first = true;
+    for (const int i : vector)
+    {
+        if (!first)
+            os<<",";
+        os<<i;
+        first = false;
+    }
+
+    os << "]";
+
+    return os;
+}
+
+int main()
+{
+    const std::vector<int> input = {1,2,3,1};
+    Solution s;
+    std::cout << "\"" << input << "\": " << (s.containsDuplicate(input) ? "true" : "false") << std::endl;
+
+    return 1;
+}

contains-duplicate/solution.hpp

@@ -0,0 +1,19 @@
+#pragma once
+
+#include <vector>
+#include <unordered_set>
+
+class Solution {
+public:
+    bool containsDuplicate(const std::vector<int>& nums) 
+    {
+        std::unordered_set<int> seen;
+        for (int i : nums)
+        {
+            if (seen.find(i) != seen.end())
+                return true;
+            seen.insert(i);
+        }
+        return false;
+    }
+};

contains-duplicate/tests.cpp

@@ -0,0 +1,34 @@
+#include <gtest/gtest.h>
+
+#include <utility>
+#include <vector>
+
+#include "solution.hpp"
+
+class ContainsDuplicatesTest :public ::testing::TestWithParam<std::pair<std::vector<int>, bool>> {
+protected:
+    Solution solution;
+};
+
+TEST_P(ContainsDuplicatesTest, CheckSolution) {
+    std::vector<int> input = std::get<0>(GetParam());
+    bool expected = std::get<1>(GetParam());
+
+    bool actual = solution.containsDuplicate(input);
+
+    EXPECT_EQ(expected, actual);
+}
+
+INSTANTIATE_TEST_CASE_P(
+        ContainsDuplicatesTests,
+        ContainsDuplicatesTest,
+        ::testing::Values(
+                std::make_pair<std::vector<int>, bool>({}, false),
+                std::make_pair<std::vector<int>, bool>({ 1 }, false),
+                std::make_pair<std::vector<int>, bool>({1, 1}, true),
+                std::make_pair<std::vector<int>, bool>({1, 2}, false),
+                std::make_pair<std::vector<int>, bool>({1,2,3,1}, true),
+                std::make_pair<std::vector<int>, bool>({1,2,3,4}, false),
+                std::make_pair<std::vector<int>, bool>({1,1,1,3,3,4,3,2,4,2}, true)
+                )
+        );