diff --git a/ch02/ex2_04.cpp b/ch02/ex2_04.cpp
index 986f2365..1f1982fa 100644
--- a/ch02/ex2_04.cpp
+++ b/ch02/ex2_04.cpp
@@ -1,4 +1,4 @@
-#include <iostream>
+#include <bits/stdc++.h>
 
 int main()
 {