Compilare: user.cpp: In function ‘bool dfs(int, int)’: user.cpp:51:37: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < g[nod].size() && !ok; ++i) ^ user.cpp: In function ‘void get_number(int&)’: user.cpp:27:43: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fread(Buffer , 1 , Bsize , stdin); ^ user.cpp:37:46: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fread(Buffer , 1 , Bsize , stdin); ^ user.cpp: In function ‘int main()’: user.cpp:63:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("ciclu2.in","r",stdin); ^ user.cpp:64:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("ciclu2.out","w",stdout); ^ user.cpp:66:38: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fread(Buffer , 1 , Bsize , stdin); p = 0; ^