Hello, how can I solve this problem when I get multiple definitions when compiling?

[CHANdaFeng]

/home/cxf/CLionProjects/CFAR/ca_cfar.cpp:8: multiple definition of CA_CFAR::getEdgeOffset(int, int, int)'; CMakeFiles/ca_cfar.dir/main.cpp.o:/home/cxf/CLionProjects/CFAR/ca_cfar.cpp:8: first defined here /usr/bin/ld: CMakeFiles/ca_cfar.dir/ca_cfar.cpp.o: in function std::vector<double, std::allocator >::vector(std::initializer_list, std::allocator const&)':
/home/cxf/CLionProjects/CFAR/ca_cfar.cpp:22: multiple definition of CA_CFAR::get_block_sum(cv::Mat&, int, int, int)'; CMakeFiles/ca_cfar.dir/main.cpp.o:/home/cxf/CLionProjects/CFAR/ca_cfar.cpp:22: first defined here /usr/bin/ld: CMakeFiles/ca_cfar.dir/ca_cfar.cpp.o: in function CA_CFAR::CA_CFAR(int, int, int, double)':
/home/cxf/CLionProjects/CFAR/ca_cfar.cpp:42: multiple definition of CA_CFAR::CA_CFAR(int, int, int, double)'; CMakeFiles/ca_cfar.dir/main.cpp.o:/home/cxf/CLionProjects/CFAR/ca_cfar.cpp:42: first defined here /usr/bin/ld: CMakeFiles/ca_cfar.dir/ca_cfar.cpp.o: in function CA_CFAR::CA_CFAR(int, int, int, double)':
/home/cxf/CLionProjects/CFAR/ca_cfar.cpp:42: multiple definition of CA_CFAR::CA_CFAR(int, int, int, double)'; CMakeFiles/ca_cfar.dir/main.cpp.o:/home/cxf/CLionProjects/CFAR/ca_cfar.cpp:42: first defined here /usr/bin/ld: CMakeFiles/ca_cfar.dir/ca_cfar.cpp.o: in function CA_CFAR::mask(cv::Mat&, cv::Mat&)':
/home/cxf/CLionProjects/CFAR/ca_cfar.cpp:49: multiple definition of CA_CFAR::mask(cv::Mat&, cv::Mat&)'; CMakeFiles/ca_cfar.dir/main.cpp.o:/home/cxf/CLionProjects/CFAR/ca_cfar.cpp:49: first defined here /usr/bin/ld: CMakeFiles/ca_cfar.dir/utils.cpp.o: in function Erosion(cv::Mat&, cv::Mat&, int)':
/home/cxf/CLionProjects/CFAR/utils.cpp:12: multiple definition of Erosion(cv::Mat&, cv::Mat&, int)'; CMakeFiles/ca_cfar.dir/main.cpp.o:/home/cxf/CLionProjects/CFAR/utils.cpp:12: first defined here /usr/bin/ld: CMakeFiles/ca_cfar.dir/utils.cpp.o: in function Dilation(cv::Mat&, cv::Mat&, int)':
/home/cxf/CLionProjects/CFAR/utils.cpp:24: multiple definition of Dilation(cv::Mat&, cv::Mat&, int)'; CMakeFiles/ca_cfar.dir/main.cpp.o:/home/cxf/CLionProjects/CFAR/utils.cpp:24: first defined here /usr/bin/ld: CMakeFiles/ca_cfar.dir/utils.cpp.o: in function build_image_array(cv::Mat&)':
/home/cxf/CLionProjects/CFAR/utils.cpp:36: multiple definition of `build_image_array(cv::Mat&)'; CMakeFiles/ca_cfar.dir/main.cpp.o:/home/cxf/CLionProjects/CFAR/utils.cpp:36: first defined here
collect2: error: ld returned 1 exit status

Hello, how can I solve this problem when I get multiple definitions when compiling?