Compilare: user.cpp: In function ‘int main()’: user.cpp:103:98: warning: operation on ‘x’ may be undefined [-Wsequence-point] else printf("%d\n", aib.query(x) + aib.query(y) - 2*aib.query(x = get_lca(x,y)) + val[x]); ^ user.cpp:103:98: warning: operation on ‘x’ may be undefined [-Wsequence-point] user.cpp:82:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("delay.in", "r", stdin); ^ user.cpp:83:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("delay.out", "w", stdout); ^ user.cpp:85:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &n); ^ user.cpp:86:45: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] for(i=1; i<=n; ++i) scanf("%d", &val[i]); ^ user.cpp:90:30: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &x, &y); ^ user.cpp:98:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &q); ^ user.cpp:101:39: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d", &type, &x, &y); ^