Fix makefile

Makefile

 
 CXXFLAGS=-std=c++17
 
-default: main
+default: bin/main
 
-main: src/calculator.cpp
+bin/main: src/calculator.cpp src/main.cpp
 	mkdir -p bin
-	$(CXX) $(CXXFLAGS) -o bin/main src/calculator.cpp src/main.cpp
+	$(CXX) $(CXXFLAGS) -o $@ $^
 
-fuzz_main: src/calculator.cpp
+bin/fuzz_main: src/calculator.cpp src/main.cpp
 	mkdir -p bin
-	afl-g++ $(CXXFLAGS) -o bin/fuzz_main src/calculator.cpp src/main.cpp
+	afl-g++ $(CXXFLAGS) -o $@ $^
 
-fuzz: fuzz_main
+fuzz: bin/fuzz_main
 	rm -rf test/out
 	afl-fuzz -i test/in -o test/out -- ./bin/fuzz_main
 
 clean:
-	rm -rf bin test/out
-	rm -rf main fuzz_main out
+	rm -rf bin
 
-tests: test/main.test.cpp
+bin/tests: test/main.test.cpp src/main.cpp
 	mkdir -p bin
-	$(CXX) $(CXXFLAGS) -o bin/tests src/main.cpp test/main.test.cpp
+	$(CXX) $(CXXFLAGS) -o $@ $^