diff --git a/week07/ex3.c b/week07/ex3.c
index 30db038..22cd211 100644
--- a/week07/ex3.c
+++ b/week07/ex3.c
@@ -1,3 +1,5 @@
+// Copied and fixed the code from goo.gl/EMpzYz
+
 #include <stdlib.h>
 #include <stdio.h>
 #include <time.h>
diff --git a/week07/ex4.c b/week07/ex4.c
index db49698..2031861 100644
--- a/week07/ex4.c
+++ b/week07/ex4.c
@@ -18,6 +18,7 @@ void* myrealloc(void* ptr, size_t prev_size, size_t new_size) {
     return res;
 }
 
+// Copied and fixed the code from goo.gl/EMpzYz
 // test myrealloc using ex3
 int main() {
 	//Allows you to generate random number
diff --git a/week07/ex5.c b/week07/ex5.c
index 3c38d8e..28ee5c8 100644
--- a/week07/ex5.c
+++ b/week07/ex5.c
@@ -1,3 +1,5 @@
+// Copied and fixed the code from the slides
+
 #include <stdio.h>
 
 int main() {