diff --git a/range_queries/mo.cpp b/range_queries/mo.cpp
index d281ef077..10abf0a96 100644
--- a/range_queries/mo.cpp
+++ b/range_queries/mo.cpp
@@ -1,4 +1,7 @@
+#include <algorithm>
+#include <cmath>
 #include <iostream>
+
 using namespace std;
 const int N = 1e6 + 5;
 int a[N], bucket[N], cnt[N];