Compilare: main.cpp: In function 'long long int Calculate(std::__cxx11::string)': main.cpp:53:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i< pattern.length(); ++i) ~^~~~~~~~~~~~~~~~~~ main.cpp: In function 'bool verifyE(std::__cxx11::string)': main.cpp:63:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i< pattern.length(); ++i) ~^~~~~~~~~~~~~~~~~~ main.cpp: In function 'int countE(std::__cxx11::string)': main.cpp:73:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i< pattern.length(); ++i) ~^~~~~~~~~~~~~~~~~~