Compilare: user.cpp: In function ‘void printMat(std::vector<std::vector<int, std::allocator<int> >, std::allocator<std::vector<int, std::allocator<int> > > >)’: user.cpp:11: warning: comparison between signed and unsigned integer expressions user.cpp:12: warning: comparison between signed and unsigned integer expressions user.cpp: In function ‘int main()’: user.cpp:49: warning: comparison between signed and unsigned integer expressions user.cpp:50: warning: comparison between signed and unsigned integer expressions user.cpp:55: warning: comparison between signed and unsigned integer expressions user.cpp:59: warning: comparison between signed and unsigned integer expressions user.cpp:66: warning: comparison between signed and unsigned integer expressions