/in/foo.cc: In function 'bool Row(int)':
/in/foo.cc:13:23: error: 'memset' was not declared in this scope
   memset(b,0,sizeof(b));
                       ^
/in/foo.cc: In function 'bool Column(int)':
/in/foo.cc:33:23: error: 'memset' was not declared in this scope
   memset(b,0,sizeof(b));
                       ^
/in/foo.cc: In function 'bool Block(int)':
/in/foo.cc:55:23: error: 'memset' was not declared in this scope
   memset(b,0,sizeof(b));
                       ^