20250324 finished.

src/problem/mod.rs

@@ -556,3 +556,5 @@ mod p2680_maximum_or;
 mod p2643_row_with_maximum_ones;
 
 mod p2116_check_if_a_parentheses_string_can_be_valid;
+
+mod p2255_count_prefixes_of_a_given_string;