diff --git a/3-lang0ll/A Gentle Introduction to LLVM IR · mcyoung.pdf b/3-lang0ll/A Gentle Introduction to LLVM IR · mcyoung.pdf
new file mode 100644
index 0000000..3d6fc02
Binary files /dev/null and b/3-lang0ll/A Gentle Introduction to LLVM IR · mcyoung.pdf differ
diff --git a/3-lang0ll/foo.c b/3-lang0ll/foo.c
index b0800e5..207f36d 100644
--- a/3-lang0ll/foo.c
+++ b/3-lang0ll/foo.c
@@ -1,3 +1,5 @@
+#include <stdio.h>
+
 void print(char * x)
 {
 	return;
@@ -11,7 +13,7 @@ int sum(int a, int b)
 int main()
 {
 	char * foo = "Hello, world!";
-	print("This is a test.");
+	printf("This is a test.");
 
 	return sum(7, 15);
 }