Set C++ standard to C++20 for Clang builds

Updated the CMake configuration to use C++20 when building with Clang on MSVC. Also included the `<compare>` header in tests and adjusted formatting for improved readability.

Author: allnes

cmake/configure.cmake

@@ -23,7 +23,7 @@ set( CMAKE_LIBRARY_OUTPUT_DIRECTORY "${CMAKE_BINARY_DIR}/lib" )
 set( CMAKE_RUNTIME_OUTPUT_DIRECTORY "${CMAKE_BINARY_DIR}/bin" )
 
 if ( MSVC AND (CMAKE_C_COMPILER_ID STREQUAL "Clang") AND (CMAKE_CXX_COMPILER_ID STREQUAL "Clang"))
-    set( CMAKE_CXX_STANDARD 17 )
+    set( CMAKE_CXX_STANDARD 20 )
 else ()
     set( CMAKE_CXX_STANDARD 23 )
 endif ()

tasks/example/tests/functional/main.cpp

@@ -1,5 +1,6 @@
 #include <gtest/gtest.h>
 
+#include <compare>
 #include <cstddef>
 #include <cstdint>
 #include <stb_library.hpp>
@@ -45,7 +46,7 @@ class NesterovARunFuncTests : public ppc::util::BaseRunFuncTests<InType, OutType
 
     TestType params = std::get<ppc::util::GTestParamIndex::kTestParams>(GetParam());
     const auto k_count = static_cast<std::vector<int>::size_type>(((width + height) / std::get<0>(params)) *
-                                                                        std::stoi(std::get<1>(params)));
+                                                                  std::stoi(std::get<1>(params)));
     input_data_ = InType(k_count * k_count, 0);
     for (std::vector<int>::size_type i = 0; i < k_count; i++) {
       input_data_[(i * k_count) + i] = 1;