Compilare: user.cpp: In function ‘int main()’: user.cpp:180:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("treap.in", "r", stdin); ^ user.cpp:181:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("treap.out", "w", stdout); ^ user.cpp: In function ‘void dfs(int, int)’: user.cpp:130:20: warning: ‘fiu’ may be used uninitialized in this function [-Wmaybe-uninitialized] if (sol[fiu] == 0) ^