View Compilation Error

0_0_14616800_25113.cpp: In function 'void add(int, int, int)':
0_0_14616800_25113.cpp:52:17: error: reference to 'hash' is ambiguous
             bit[hash(i*MA+j)]+=val;
                 ^
0_0_14616800_25113.cpp:14:5: note: candidates are: int hash(int)
 int hash(int x) 
     ^
In file included from GCC4.9.2/x86_64-w64-mingw32/include/c++/bits/basic_string.h:3068:0,
                 from GCC4.9.2/x86_64-w64-mingw32/include/c++/string:52,
                 from GCC4.9.2/x86_64-w64-mingw32/include/c++/random:40,
                 from GCC4.9.2/x86_64-w64-mingw32/include/c++/bits/stl_algo.h:66,
                 from GCC4.9.2/x86_64-w64-mingw32/include/c++/algorithm:62,
                 from 0_0_14616800_25113.cpp:4:
GCC4.9.2/x86_64-w64-mingw32/include/c++/bits/functional_hash.h:58:12: note:                 template<class _Tp> struct std::hash
     struct hash;
            ^