Compilare: user.cpp: In function ‘interval update(int, int, int)’: user.cpp:47:110: warning: left operand of comma operator has no effect [-Wunused-value] arbint[node].sum_max=(a.sum_max,max(arbint[2*node+1].sum_max,a.sum_end+arbint[2*node+1].sum_start)); ^ user.cpp: In function ‘int main()’: user.cpp:87:33: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("maxq.in","r",stdin); ^ user.cpp:88:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("maxq.out","w",stdout); ^ user.cpp:90:19: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&n); ^ user.cpp:92:26: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&v[i]); ^ user.cpp:94:19: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&m); ^ user.cpp:97:33: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d",&p,&x,&y); ^