Compilare: main.cpp: In function 'int main()': main.cpp:89:30: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::vector<long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare] 89 | for(int i = 0; i < ans.size(); i++) { | ~~^~~~~~~~~~~~ main.cpp:90:34: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 90 | for(int j = 0; j < ans[i].size(); j++) { | ~~^~~~~~~~~~~~~~~