View Compilation Error

0_0_38548273_18361.cpp: In function 'int main()':
0_0_38548273_18361.cpp:63:18: error: cannot convert 'std::vector<node>*' to 'char*' for argument '1' to 'ui BKDRhash(char*)'
    key=BKDRhash(s)%N;
                  ^