Compilare: user.cpp: In function ‘int main()’: user.cpp:51:43: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if ( in( t.x + dx[i], n ) && in( t.y + dy[i], n ) ) ^ user.cpp:20:39: note: in definition of macro ‘in’ # define in( x, a ) ( unsigned( x ) < a ) ^ user.cpp:51:67: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if ( in( t.x + dx[i], n ) && in( t.y + dy[i], n ) ) ^ user.cpp:20:39: note: in definition of macro ‘in’ # define in( x, a ) ( unsigned( x ) < a ) ^ user.cpp:78:43: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if ( in( t.x + dx[i], n ) && in( t.y + dy[i], n ) ) ^ user.cpp:20:39: note: in definition of macro ‘in’ # define in( x, a ) ( unsigned( x ) < a ) ^ user.cpp:78:67: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if ( in( t.x + dx[i], n ) && in( t.y + dy[i], n ) ) ^ user.cpp:20:39: note: in definition of macro ‘in’ # define in( x, a ) ( unsigned( x ) < a ) ^