Compilare: main.cpp: In function 'int main()': main.cpp:25:10: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 25 | if (j == a.size() - 1) { | ~~^~~~~~~~~~~~~~~ main.cpp:35:23: warning: comparison of integer expressions of different signedness: 'size_t' {aka 'long unsigned int'} and 'int' [-Wsign-compare] 35 | for (size_t e = 0; e < pin && e < 1000; e++) | ~~^~~~~