diff --git a/4.cpp b/4.cpp
index b1aa1f3..c7ce065 100644
--- a/4.cpp
+++ b/4.cpp
@@ -8,13 +8,14 @@ int a(){
 	char buff[10];
 	printf("buff position: %p\n", buff);
 	printf("buff2 position: %p\n", buff2);
-	scanf("%d", &position);
+	scanf("%d\n", &position);
 	if(position < 0){
 		printf("nice try...\n");
 		exit(1);	
 	}
 	position = position*2;
-	while(position < 10 && in){
+	in = 0;
+	while(position < 10 && in != '\n'){
 		scanf("%c", &in);
 		buff[position] = in;
 		printf("%d\n", position);
diff --git a/Makefile b/Makefile
index d9015b9..b9b1f46 100644
--- a/Makefile
+++ b/Makefile
@@ -2,6 +2,6 @@ all:
 	g++ -I./ -g -o 1.bin -fstack-protector-all 1.cpp
 	g++ -I./ -g -o 2.bin -fstack-protector-all 2.cpp
 	g++ -I./ -g -o 3.bin -fstack-protector-all 3.cpp
-	g++ -I./ -g -o 4.bin -fstack-protector-all 4.cpp
+	g++-4.8 -I./ -g -o 4.bin -fsanitize=address 4.cpp
 clean:
 	rm -f *.bin *.o *.so *_expanded.cpp