Compilare: user.cpp: In function ‘int main()’: user.cpp:16:30: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("taxa.in","r",stdin); ^ user.cpp:17:32: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("taxa.out","w",stdout); ^ user.cpp:18:45: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d%d%d%d",&n,&m,&sx,&sy,&ex,&ey); ^ user.cpp:22:22: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",a[i]+j); ^