Compilare: user.cpp: In function ‘void solve()’: user.cpp:71:25: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (sol.size() != n-1) { ^ user.cpp: In function ‘void adv()’: user.cpp:36:34: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fread(buf, 1, DIM, stdin); ^ user.cpp: In function ‘int main()’: user.cpp:81:40: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("permsplit.in", "r", stdin); ^ user.cpp:82:42: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("permsplit.out", "w", stdout); ^ user.cpp:84:30: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fread(buf, 1, DIM, stdin); ^