Compilare: main.cpp: In function 'int main()': main.cpp:27:25: warning: array subscript has type 'char' [-Wchar-subscripts] frecv[sir[i]]++; ^ main.cpp:30:70: warning: array subscript has type 'char' [-Wchar-subscripts] sum[i] = sum[i + 1] + 1ll * nrLitere - 1ll * frecv[sir[i]]; ^ main.cpp:40:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < sir.size(); i++) ~~^~~~~~~~~~~~