Compilare: user.cpp: In function ‘int main()’: user.cpp:84:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("mindist.in","r",stdin); ^ user.cpp:85:39: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("mindist.out","w",stdout); ^ user.cpp:86:19: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&n); ^ user.cpp:99:30: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d",&v1,&v2); ^ user.cpp:89:29: warning: iteration 100002u invokes undefined behavior [-Waggressive-loop-optimizations] tree[0][i]=newnode(); ^ user.cpp:87:5: note: containing loop for(int i=1;i<=200000;i++) ^