Mine

CFLAGS=-Wall -g

all: program

program: question9_mastermind_main.o question9_mastermind_functions.o
        $(LD) -o $@ $^

question9_mastermind_main.o: question9_mastermind_main.c

question9_mastermind_functions.o: question9_mastermind_functions.c

clean:
        rm -f question9_mastermind_main.o question9_mastermind_functions.o