Compilare: main.cpp: In function 'int main()': main.cpp:71:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 71 | for(int j=1; j<lin[i].size(); j++) | ~^~~~~~~~~~~~~~ main.cpp:77:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 77 | for(int j=1; j<col[i].size(); j++) | ~^~~~~~~~~~~~~~