Compilare: user.cpp: In function ‘long long int secv(int)’: user.cpp:85:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for ( int i = 1; i < P.size(); ++i) ~~^~~~~~~~~~ user.cpp: In function ‘int main()’: user.cpp:24:31: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("secv5.in","r",stdin); ^ user.cpp:25:33: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("secv5.out","w",stdout); ^ user.cpp: In function ‘void Next()’: user.cpp:97:46: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] std::fread(buf, 1, Lim, stdin), u = 0; ^