Compilare: main.cpp: In function 'int main()': main.cpp:27:21: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 27 | for(int i = 0;i < a.size(); ++i) dp[i+1][i+1] = 3,dp[i+1][i] = 0; | ~~^~~~~~~~~~ main.cpp:28:21: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 28 | for(int i = 1;i < a.size(); ++i) | ~~^~~~~~~~~~ main.cpp:30:25: warning: comparison of integer expressions of different signedness: 'long long int' and 'long long unsigned int' [-Wsign-compare] 30 | for(int j = 0;j < a.size() - i ; ++j) | ~~^~~~~~~~~~~~~~