Compilare: main.cpp: In function 'int main()': main.cpp:36:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < s.size() - 2; i++) ~~^~~~~~~~~~~~~~ main.cpp:40:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while (cnt != s.size() + 2) ~~~~^~~~~~~~~~~~~~~ main.cpp:42:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < s.size() - cnt; i++) ~~^~~~~~~~~~~~~~~~