Compilare: main.cpp: In function 'int main()': main.cpp:11:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < s.size(); ++i) ~~^~~~~~~~~~ main.cpp:12:18: warning: array subscript has type 'char' [-Wchar-subscripts] ++fv[s[i]]; ^ main.cpp:13:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < s.size(); ++i) { ~~^~~~~~~~~~ main.cpp:20:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (maxap > s.size() / 2) { ~~~~~~^~~~~~~~~~~~~~ main.cpp:26:58: warning: suggest parentheses around '&&' within '||' [-Wparentheses] if ((rez == "" || (j != rez[rez.size() - 1]) && fv[j] > 0)) { ~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~