Compilare: main.cpp: In function 'int main()': main.cpp:14:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(size_t i = 1;i<=n;++i){ ~^~~ main.cpp:8:32: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("nim.in","r",stdin); ^ main.cpp:9:34: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("nim.out","w",stdout); ^