Here take solving a problem "a" as example.
- code in ./src/a.cpp.
- build the exe with CMake, paste the samples in ./input/a/0.in and ./output/a/0.out.
- run the following command to get the result of the test case 0
./test.sh a 0
- you may add more test cases to debug, run the following command for all cases and compare them with the standard output
./test.sh a
VScode还是用不来（