Compilare: main.cpp: In function 'int main()': main.cpp:75:29: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::vector<int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare] 75 | for (int ii = 0; ii < lev.size(); ++ii) | ~~~^~~~~~~~~~~~ main.cpp:79:29: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 79 | for (int ii = 0; ii < lev[0].size(); ++ii) | ~~~^~~~~~~~~~~~~~~ main.cpp:84:29: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::vector<int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare] 84 | for (int ii = 1; ii < lev.size(); ++ii) | ~~~^~~~~~~~~~~~ main.cpp:86:37: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 86 | for (int jj = 1; jj < lev[ii].size(); ++jj) | ~~~^~~~~~~~~~~~~~~~