Compilare: main.cpp: In function 'int main()': main.cpp:85:26: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 85 | for(int j = 1; j < el[i].size(); j++) | ~~^~~~~~~~~~~~~~ main.cpp:92:26: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 92 | for(int j = 1; j < el[i].size() - 1; j++) | ~~^~~~~~~~~~~~~~~~~~