Compilare: main.cpp: In function 'll fa(std::string&)': main.cpp:13:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 13 | for(int j = 0 ; j <= a.size() ; ++j) dp[i][j] = 0; | ~~^~~~~~~~~~~ main.cpp:18:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 18 | for(int j = 1 ; j <= a.size(); ++j) | ~~^~~~~~~~~~~