Compilare: user.cpp: In function ‘int dfs(int)’: user.cpp:42:41: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < node[nod].v.size(); i ++) ^ user.cpp: In function ‘int main()’: user.cpp:72:36: 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:73:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &n); ^ user.cpp:76:32: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &n1, &n2); ^ user.cpp:82:34: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &node[i].key); ^ user.cpp:84:39: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &node[i].priority); ^