Compilare: main.cpp: In member function 'int Grammar::was_A(int)': main.cpp:11:37: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 11 | int was_A(int left) { return left < v.size() ? left + 1 : 0; } | ~~~~~^~~~~~~~~~ main.cpp: In member function 'int Grammar::was_B(int)': main.cpp:14:14: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 14 | if (left >= v.size()) | ~~~~~^~~~~~~~~~~ main.cpp:18:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 18 | if (left + 4 >= v.size()) | ~~~~~~~~~^~~~~~~~~~~ main.cpp: In member function 'bool Grammar::was_C(int)': main.cpp:26:14: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 26 | if (left >= v.size()) | ~~~~~^~~~~~~~~~~ main.cpp:31:18: warning: comparison of integer expressions of different signedness: 'std::vector<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare] 31 | if (v.size() > left + 1 && v[left] == 1 && v[left + 1] == 2) | ~~~~~~~~~^~~~~~~~~~ main.cpp: In member function 'bool Grammar::check(std::vector<int>&)': main.cpp:47:21: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 47 | return was_A(0) == v.size() || was_B(0) == v.size() || was_C(0) == v.size(); | ~~~~~~~~~^~~~~~~~~~~ main.cpp:47:45: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 47 | return was_A(0) == v.size() || was_B(0) == v.size() || was_C(0) == v.size(); | ~~~~~~~~~^~~~~~~~~~~