Compilare: user.cpp: In function ‘int main()’: user.cpp:72: warning: comparison between signed and unsigned integer expressions user.cpp:74: warning: comparison between signed and unsigned integer expressions user.cpp: In function ‘void fill_with_decomposition(std::vector<std::vector<int, std::allocator<int> >, std::allocator<std::vector<int, std::allocator<int> > > >&, std::vector<int, std::allocator<int> >&, int)’: user.cpp:165: warning: comparison between signed and unsigned integer expressions