Update README.md

Author: 2017pxy

README.md

@@ -46,7 +46,7 @@ by our team.
 + **General and extensible data structure.** We design general and extensible data structures to unify the formatting and
 usage of various recommendation datasets.
 
-+ **Comprehensive benchmark models and datasets.** We implement 77 commonly used recommendation algorithms, and provide
++ **Comprehensive benchmark models and datasets.** We implement 78 commonly used recommendation algorithms, and provide
 the formatted copies of 28 recommendation datasets.
 
 + **Efficient GPU-accelerated execution.** We optimize the efficiency of our library with a number of improved techniques