Compilare: main.cpp: In function 'int determinare_litere_prefix(int&)': main.cpp:18:16: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i = 0; i < Sir.size(); ++i) { ~~^~~~~~~~~~~~ main.cpp: In function 'int parcurgere_sir(int, int)': main.cpp:32:13: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while (poz < Sir.size()) { ~~~~^~~~~~~~~~~~ main.cpp:36:14: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (; poz < Sir.size() && ++num_poz <= num_lit; ++poz) { ~~~~^~~~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:68:17: warning: ignoring return value of 'int system(const char*)', declared with attribute warn_unused_result [-Wunused-result] system("PAUSE"); ^