This must be a C program.

Given two directories ./a and ./b, passed as parameters to your program, you need to synchronize them, as follows: o If a file in a does not exist in directory b, you should replicate it in directory b. o If a file in b does not exist in directory a, it should be deleted from directory b. o If a file exists in both directories a and b, the file with the most recent modified date / time should be copied from one directory to the other