How to create dependencies in CMake - c++

Question

I'm trying to improve my project layout.
Here's (some of) my CMakeLists.txt files:
project(Numerical CXX)
include(cotire)
cmake_minimum_required(VERSION 3.1)
set (CMAKE_CXX_STANDARD 14)
add_executable(hw1 hw1.cpp
linalg/lu.cpp
linalg/banded.cpp
)
add_executable(hw2 hw2.cpp
linalg/cholesky.cpp
linalg/lu.cpp
linalg/banded.cpp
)
add_executable(hw3 hw3.cpp
linalg/solvers-new.cpp
linalg/cholesky.cpp
linalg/lu.cpp
linalg/banded.cpp
)
...
lu.h includes banded.h, so anything that needs lu will also need banded. This requires redundancy in my project as seen above. Is there a way that I don't have to add banded.cpp every time I add lu.cpp?

Answer 1

#Amadeus's answer works, but I think a better answer is to take the common files and move them into a library:
project(Numerical CXX)
include(cotire)
cmake_minimum_required(VERSION 3.1)
set (CMAKE_CXX_STANDARD 14)
add_library(CommonLib STATIC
linalg/lu.cpp
linalg/banded.cpp
)
add_executable(hw1
hw1.cpp
)
target_link_libraries(hw1 LINK_PUBLIC
CommonLib
)
add_executable(hw2
hw2.cpp
linalg/cholesky.cpp
)
target_link_libraries(hw2 LINK_PUBLIC
CommonLib
)
add_executable(hw3
hw3.cpp
linalg/solvers-new.cpp
linalg/cholesky.cpp
)
target_link_libraries(hw3 LINK_PUBLIC
CommonLib
)