Compilare: main.cpp: In function 'bool vf(int)': main.cpp:28:28: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 28 | for(int i = lung; i<a[sir].size(); ++i) | ~^~~~~~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:61:11: warning: 'ans' may be used uninitialized [-Wmaybe-uninitialized] 61 | fout<<ans; | ^~~ main.cpp:53:9: note: 'ans' was declared here 53 | int ans; | ^~~