Compilare: user.cpp: In function ‘int main()’: user.cpp:74:39: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("manhattan.in","r",stdin); ^ user.cpp:75:41: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("manhattan.out","w",stdout); ^ user.cpp:80:51: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%d%d%d%d",&z1.l1,&z1.c1,&z1.l2,&z1.c2); ^ user.cpp:81:51: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%d%d%d%d",&z2.l1,&z2.c1,&z2.l2,&z2.c2); ^