/in/foo.cc: In constructor 'BigNumber::BigNumber()':
/in/foo.cc:13:23: error: 'memset' was not declared in this scope
   memset(N, 0, MAX_LEN);
                       ^
/in/foo.cc: In constructor 'BigNumber::BigNumber(int)':
/in/foo.cc:18:23: error: 'memset' was not declared in this scope
   memset(N, 0, MAX_LEN);
                       ^
/in/foo.cc: In copy constructor 'BigNumber::BigNumber(const BigNumber&)':
/in/foo.cc:27:25: error: 'memcpy' was not declared in this scope
   memcpy(N, n.N, MAX_LEN);
                         ^
/in/foo.cc: In member function 'void BigNumber::clear()':
/in/foo.cc:34:23: error: 'memset' was not declared in this scope
   memset(N, 0, MAX_LEN);
                       ^
/in/foo.cc: In member function 'void BigNumber::mul10(int)':
/in/foo.cc:38:22: error: 'memmove' was not declared in this scope
   memmove(N + n, N, n);
                      ^
/in/foo.cc: In member function 'BigNumber& BigNumber::operator+=(const BigNumber&)':
/in/foo.cc:61:27: error: '__max' was not declared in this scope
   int L = __max(len, o.len);
                           ^