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+# Intro. to OS HW1
+
+## Docker Compose usage
+
+Install docker and docker-compose if not installed.
+
+1. Change uid / gid to yours in `Dockerfile` and `docker-compose.yaml`.
+2. Run `docker compose build` to build Docker image.
+3. Run `docker compose run test` to launch testing environment.
+
+## Makefile
+
+First, `cd` into `code` directory.
+
+- `make clean` to clean previous build.
+- `make` to build.
+- `make run` to run tests.