Compilare: user.cpp: In function ‘int main()’: user.cpp:62:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("arbvalmax.in", "r", stdin); ^ user.cpp:63:40: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("arbvalmax.out", "w", stdout); ^ user.cpp:65:48: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] int N, numQuery; scanf("%d%d", &N, &numQuery); ^ user.cpp:69:31: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] int dad; scanf("%d", &dad); ^ user.cpp:74:25: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &key[i]); ^ user.cpp:114:36: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] int u, v; scanf("%d%d", &u, &v); -- u; -- v; ^