Added gitignore and makefile

.gitignore

@@ -0,0 +1,5 @@
+/.vscode
+
+# Build files and final binary
+/build
+test

Makefile

@@ -0,0 +1,47 @@
+TARGET_EXEC := test
+BUILD_DIR := ./build
+SRC_DIRS := ./src
+
+# False targets
+# (these are the only ones you manually run)
+all: $(TARGET_EXEC)
+
+run: all
+	./$(TARGET_EXEC)
+
+clean:
+	-rm -r $(BUILD_DIR)
+	@echo ""
+
+.PHONY: clean all run
+
+#################################################
+# Flags and autodetection
+
+# -MMD and -MP generate makefiles with extension .d.
+CPPFLAGS := -Wall -MMD -MP -I src
+LDFLAGS := -l fftw3
+
+# Find all cpp files in source dirs
+SRCS := $(shell find $(SRC_DIRS) -name '*.cpp')
+# Turns ./build/a.cpp into ./build/a.cpp.o
+OBJS := $(SRCS:%=$(BUILD_DIR)/%.o)
+# Turns ./build/a.cpp.o into ./build/a.cpp.d
+DEPS := $(OBJS:.o=.d)
+
+#################################################
+# Build targets
+
+# C++ build step
+$(BUILD_DIR)/%.cpp.o: %.cpp
+	mkdir -p $(dir $@)
+	g++ $(CPPFLAGS) $(CXXFLAGS) -c $< -o $@
+
+
+# Final build step
+$(TARGET_EXEC) : $(OBJS)
+	g++ $(OBJS) -o $@ $(LDFLAGS)
+
+
+# Include generated makefiles
+-include $(DEPS)