Compilare: main.cpp: In function 'void dfs(int)': main.cpp:57:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i + 1 < d.size (); i++) { ~~~~~~^~~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:111:40: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen ("aliniate.in", "r", stdin); ^ main.cpp:112:42: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen ("aliniate.out", "w", stdout); ^