Compilare: main.cpp: In function 'int main()': main.cpp:24:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < a.size(); i++) ~~^~~~~~~~~~ main.cpp:27:35: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int j = 0; j < a.size(); j++) { ~~^~~~~~~~~~ main.cpp:28:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while (j < a.size() && (a[i] == a[j] || a[j] == '*')) { ~~^~~~~~~~~~