Compilare: main.cpp: In function 'int main()': main.cpp:46:32: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen(infile, "r", stdin); ^ main.cpp:47:34: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen(outfile, "w", stdout); ^ main.cpp:49:20: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &n); ^ main.cpp:53:31: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d", &x, &y); ^ main.cpp: In function 'std::pair<int, int> find_first_node(int)': main.cpp:17:24: warning: 'best_node' may be used uninitialized in this function [-Wmaybe-uninitialized] int max_depth = 0, best_node; ^~~~~~~~~