Compilare: user.cpp: In function ‘int main()’: user.cpp:35:40: warning: operation on ‘k’ may be undefined [-Wsequence-point] v[++k].lin=v[k-1].lin+1; ^ user.cpp:41:44: warning: operation on ‘k’ may be undefined [-Wsequence-point] v[++k].col=v[k-1].col+1; ^ user.cpp:47:48: warning: operation on ‘k’ may be undefined [-Wsequence-point] v[++k].lin=v[k-1].lin-1; ^ user.cpp:53:52: warning: operation on ‘k’ may be undefined [-Wsequence-point] v[++k].col=v[k-1].col-1; ^