Compilare: user.cpp: In function ‘int main()’: user.cpp:35:95: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while (!Stack.empty() && Stack.top() < Str[idx] && Stack.size() + (int)Str.size() - idx + 1 >= M) ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~ user.cpp:37:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (Stack.size() < M) ~~~~~~~~~~~~~^~~