Compilare: user.cpp: In function ‘int rest(std::vector<char>)’: user.cpp:12:25: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i = 0; i < V.size(); i++) ^ user.cpp: In function ‘int main()’: user.cpp:67:29: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i = 0; i < sol.size(); i++) ^ user.cpp:57:32: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("cifre4.in","r",stdin); ^ user.cpp:58:34: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("cifre4.out","w",stdout); ^ user.cpp:59:16: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&T); ^ user.cpp:62:22: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d",&N,&P); ^