Compilare: user.cpp: In function ‘void spirala(int, int, std::vector<std::vector<int> >)’: user.cpp:109:9: warning: ‘b’ may be used uninitialized in this function [-Wmaybe-uninitialized] o<<b; ^ user.cpp:40:25: warning: ‘l’ may be used uninitialized in this function [-Wmaybe-uninitialized] int m1=0,n1=0,k,d=1,l; ^ user.cpp:40:19: warning: ‘k’ may be used uninitialized in this function [-Wmaybe-uninitialized] int m1=0,n1=0,k,d=1,l; ^