Compilare: main.cpp: In function 'int main()': main.cpp:47:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare] 47 | while(ind < mars[i].size() && mars[i][ind].first == j) add += mars[i][ind].second, ind++; | ~~~~^~~~~~~~~~~~~~~~ main.cpp:40:9: warning: unused variable 'flag' [-Wunused-variable] 40 | int flag = 0; | ^~~~