Build command failed.
Error while executing process C:\Users\Ruslan\AppData\Local\Android\Sdk\cmake\3.6.4111459\bin\cmake.exe with arguments {--build C:\Users\Ruslan\AndroidStudioProjects\Telnet\app\.externalNativeBuild\cmake\debug\x86_64 --target helloworld-c}
[1/1] Linking CXX shared library ..\..\..\..\build\intermediates\cmake\debug\obj\x86_64\libhelloworld-c.so
FAILED: cmd.exe /C "cd . && C:\Users\Ruslan\AppData\Local\Android\Sdk\ndk-bundle\toolchains\llvm\prebuilt\windows-x86_64\bin\clang++.exe  --target=x86_64-none-linux-android22 --gcc-toolchain=C:/Users/Ruslan/AppData/Local/Android/Sdk/ndk-bundle/toolchains/llvm/prebuilt/windows-x86_64 --sysroot=C:/Users/Ruslan/AppData/Local/Android/Sdk/ndk-bundle/toolchains/llvm/prebuilt/windows-x86_64/sysroot -fPIC -g -DANDROID -fdata-sections -ffunction-sections -funwind-tables -fstack-protector-strong -no-canonical-prefixes -D_FORTIFY_SOURCE=2 -Wformat -Werror=format-security   -O0 -fno-limit-debug-info  -Wl,--exclude-libs,libgcc_real.a -Wl,--exclude-libs,libatomic.a -static-libstdc++ -Wl,--build-id -Wl,--fatal-warnings -Wl,--no-undefined -Qunused-arguments  -u ANativeActivity_onCreate -shared -Wl,-soname,libhelloworld-c.so -o ..\..\..\..\build\intermediates\cmake\debug\obj\x86_64\libhelloworld-c.so CMakeFiles/helloworld-c.dir/src/cpp/helloworld-c.cpp.o  -landroid libnative_app_glue.a -llog -latomic -lm && cd ."
C:\Users\Ruslan/AppData\Local\Android\Sdk\ndk-bundle\sources\android\native_app_glue\android_native_app_glue.c:233: error: undefined reference to 'android_main'

clang++: error: linker command failed with exit code 1 (use -v to see invocation)

ninja: build stopped: subcommand failed.