diff --git a/chapters/intro-computer-architecture/binary-hex/drills/tasks/rotations/solution/rotations.c b/chapters/intro-computer-architecture/binary-hex/drills/tasks/rotations/solution/rotations.c
index 1eaa3140..5f5f30d7 100644
--- a/chapters/intro-computer-architecture/binary-hex/drills/tasks/rotations/solution/rotations.c
+++ b/chapters/intro-computer-architecture/binary-hex/drills/tasks/rotations/solution/rotations.c
@@ -2,7 +2,7 @@
 
 #include <stdio.h>
 
-void rotate_left(int *number, int bits)
+void rotate_left(unsigned int *number, int bits)
 {
 	unsigned int bit_mask = -1;
 
@@ -13,7 +13,7 @@ void rotate_left(int *number, int bits)
 	(*number) |= bit_mask;
 }
 
-void rotate_right(int *number, int bits)
+void rotate_right(unsigned int *number, int bits)
 {
 	unsigned int bit_mask = -1;
 
@@ -26,7 +26,7 @@ void rotate_right(int *number, int bits)
 
 int main(void)
 {
-	int number;
+	unsigned int number;
 
 	number = 0x80000000;
 	rotate_left(&number, 1);
diff --git a/chapters/intro-computer-architecture/binary-hex/drills/tasks/rotations/support/rotations.c b/chapters/intro-computer-architecture/binary-hex/drills/tasks/rotations/support/rotations.c
index 134ea8ec..929c3db4 100644
--- a/chapters/intro-computer-architecture/binary-hex/drills/tasks/rotations/support/rotations.c
+++ b/chapters/intro-computer-architecture/binary-hex/drills/tasks/rotations/support/rotations.c
@@ -2,14 +2,14 @@
 
 #include <stdio.h>
 
-void rotate_left(int *number, int bits)
+void rotate_left(unsigned int *number, int bits)
 {
 	/* TODO */
 	(void) number;
 	(void) bits;
 }
 
-void rotate_right(int *number, int bits)
+void rotate_right(unsigned int *number, int bits)
 {
 	/* TODO */
 	(void) number;