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@@ -1,4 +1,3 @@
-
 ##
 
 **binary search**
@@ -13,7 +12,7 @@
 
 **bipartite graph**
 
-**mathematical method**: quickpow, prime judging, greatest common divisor
+**math**: quickpow, prime judging, greatest common divisor
 
 **binary indexed tree**