Compilare: user.cpp: In function ‘int main()’: user.cpp:16:124: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d%d",&b.x1,&b.y1,&b.x2,&b.y2),scanf("%d%d%d%d",&c.x1,&c.y1,&c.x2,&c.y2),x=R(a,b),y=R(a,c),z=R(b,c),t=R(x,c); ^ user.cpp:16:124: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] user.cpp:16:124: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] user.cpp:16:124: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] user.cpp:16:124: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]