diff --git a/divide_and_conquer/karatsuba_algorithm_for_fast_multiplication.cpp b/divide_and_conquer/karatsuba_algorithm_for_fast_multiplication.cpp
index f80d00272..dc8b67b19 100644
--- a/divide_and_conquer/karatsuba_algorithm_for_fast_multiplication.cpp
+++ b/divide_and_conquer/karatsuba_algorithm_for_fast_multiplication.cpp
@@ -11,7 +11,6 @@
 #include <cassert>   /// for assert
 #include <iostream>  /// for IO operations
 #include <vector>    /// for std::vector
-#include <string>    /// for string
 #include <cstring>   /// for string
 
 /**