diff --git a/2015/endoh4/Makefile b/2015/endoh4/Makefile
index 67b708fd5..b916651f9 100644
--- a/2015/endoh4/Makefile
+++ b/2015/endoh4/Makefile
@@ -63,20 +63,21 @@ X11_INCDIR= /opt/X11/include
 # Common C compiler warnings to silence
 #
 #CSILENCE=
-CSILENCE= -Wno-error -Wno-implicit-function-declaration -Wno-main -Wno-return-type
+CSILENCE= -Wno-error -Wno-implicit-function-declaration -Wno-implicit-int \
+	-Wno-main -Wno-pedantic -Wno-return-type
 
 # Common C compiler warning flags
 #
 #CWARN= ${CSILENCE}
 #CWARN= -Wall ${CSILENCE}
-CWARN= -Wall -Wextra ${CSILENCE}
-#CWARN= -Wall -Wextra -pedantic ${CSILENCE}
+#CWARN= -Wall -Wextra ${CSILENCE}
+CWARN= -Wall -Wextra -pedantic ${CSILENCE}
 
 # Compiler standard
 #
 #CSTD=
 #CSTD= -ansi
-CSTD= -std=gnu90
+CSTD= -std=gnu11
 
 # Compiler bit architecture
 #
@@ -101,8 +102,8 @@ CINCLUDE=
 #CINCLUDE= -include stdlib.h
 #CINCLUDE= -include stdio.h
 #CINCLUDE= -include stdlib.h -include stdio.h
-#CINCLUDE= -I ${X11_INCDIR}
-#CINCLUDE= -I ${HOMEBREW_PREFIX}/include/SDL2
+#CINCLUDE= -I ${X11_INCDIR} -I ${X11_INCDIR}/X11
+#CINCLUDE= `${SDL2_CONFIG} --cflags`
 
 # Optimization
 #
@@ -126,7 +127,7 @@ CFLAGS= ${CSTD} ${CWARN} ${ARCH} ${CDEFINE} ${CINCLUDE} ${OPT}
 LIBS=
 #LIBS= -lm
 #LIBS= -L ${X11_LIBDIR} -lX11
-#LIBS= -L ${HOMEBREW_PREFIX}/lib -lSDL
+#LIBS= `${SDL2_CONFIG} --libs`
 
 # C compiler to use
 #
@@ -138,8 +139,8 @@ CC= cc
 #
 ifeq ($(CC),clang)
 #
-CSILENCE+= -Wno-comma -Wno-missing-prototypes -Wno-pedantic \
-	-Wno-poison-system-directories -Wno-strict-prototypes
+CSILENCE+= -Wno-comma -Wno-missing-prototypes -Wno-poison-system-directories \
+	-Wno-strict-prototypes
 #
 CWARN+= -Weverything
 #
@@ -167,8 +168,8 @@ OBJ= ${PROG}.o
 DATA=
 TARGET= ${PROG}
 #
-ALT_OBJ= ${PROG}.alt.o
-ALT_TARGET= ${PROG}.alt
+ALT_OBJ=
+ALT_TARGET=
 
 
 #################
@@ -185,9 +186,6 @@ all: data ${TARGET}
 ${PROG}: ${PROG}.c
 	${CC} ${CFLAGS} $< -o $@ ${LIBS}
 
-${PROG}.alt: ${PROG}.alt.c
-	${CC} ${CFLAGS} $< -o $@ ${LIBS}
-
 # alternative executable
 #
 alt: data ${ALT_TARGET}
@@ -327,4 +325,3 @@ pluto: charon
 	@echo "dwarf is a type of planet"
 	@echo "therefore, $@ is a planet"
 	@echo "having lots of planets is good feature because supernovae can help ${MAKE} a lot of them"
-
diff --git a/2015/endoh4/README.md b/2015/endoh4/README.md
index 2322d9c68..321b74aab 100644
--- a/2015/endoh4/README.md
+++ b/2015/endoh4/README.md
@@ -1,38 +1,47 @@
 # Best One-liner
 
-Yusuke Endoh  
-<https://github.com/mame/>  
-Twitter: @mametter  
+    Yusuke Endoh  
+    <https://github.com/mame/>  
+    Twitter: @mametter  
 
-## To build:
+# To build:
 
-        make all
+```sh
+make
+```
 
-### To run
+### To run:
 
-    ./prog <a number of arguments>
+```sh
+./prog <a number of arguments>
+```
 
 ### Try:
 
-    ./prog @ @ @ @ @ @
+```sh
+./prog @ @ @ @ @ @
 
-    ./prog @ @ @ @ @ @ @ @ @ @ @ @
+./prog @ @ @ @ @ @ @ @ @ @ @ @
 
-    ./prog $(perl -e 'print "@ " x (2*3*5*7);')
+./prog $(perl -e 'print "@ " x (2*3*5*7);')
 
-    ./prog $(< Makefile)
+./prog $(< Makefile)
+```
 
 ### Alternate code
 
-An alternate version of this entry, prog.alt.c, is provided.  This alternate code does not contain improvements suggested by Gil Dogon.
+An alternate version of this entry, `prog.alt.c`, is provided.  
+This alternate code does not contain improvements suggested by Gil Dogon.
 
 To compile this alternate version:
 
-    make alt
+```sh
+make alt
+```
 
 Use `prog.alt` as you would `prog` above.
 
-### Selected Judges Remarks:
+## Judges' comments:
 
 For this one liner it is best to avoid prime numbers. The output groups
 factors in the x-y dimensions. How many factors can be represented before you
@@ -56,11 +65,10 @@ Inspired by [Animated Factorization Diagrams](http://www.datapointed.net/visuali
 
 EDIT: `prog.alt.c` is the original version that I submitted.  Gil Dogon kindly improved it during the review.  Thank you!
 
---------------------------------------------------------------------------------
-<!--
+## Copyright:
+
 (c) Copyright 1984-2016, [Leo Broukhis, Simon Cooper, Landon Curt Noll][judges] - All rights reserved
 This work is licensed under a [Creative Commons Attribution-ShareAlike 3.0 Unported License][cc].
 
 [judges]: http://www.ioccc.org/judges.html
 [cc]: http://creativecommons.org/licenses/by-sa/3.0/
--->