- Cheanged spaces to tabs in Makefile.

os/ass4/Makefile

-PROG = philosophers
+PROG	= philosophers
 
-CC = gcc
-CFLAGS = -ansi -Wall -Wextra -O3 -pthread
-OFILES = host.o
-RM = rm -f
+CC		= gcc
+CFLAGS	= -ansi -Wall -Wextra -O3 -pthread
+OFILES	= host.o
+RM		= rm -f
 
 $(PROG): $(OFILES)
 	$(CC) -o $(PROG) $(OFILES) $(CFLAGS)