Compilare: main.cpp: In function 'int main()': main.cpp:19:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < s.size(); ++i){ ~~^~~~~~~~~~ main.cpp:34:44: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(s[i + 1] == '<' || i + 1 == s.size()){ ~~~~~~^~~~~~~~~~~