Compilare: main.cpp: In function 'long long int GetPal()': main.cpp:17:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i = 0 ; i < v.size() ; ++ i) { ~~^~~~~~~~~~ main.cpp:22:24: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while (i + pos < v.size() && i - pos >= 0 && v[i - pos] == v[i + pos]) ~~~~~~~~^~~~~~~~~~ main.cpp:31:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i = 0 ; i < v.size() ; ++ i) { ~~^~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:39:38: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("pscpld.in", "r", stdin) ; ^ main.cpp:40:40: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("pscpld.out", "w", stdout) ; ^