Compilare: user.cpp: In function ‘int main()’: user.cpp:17:15: warning: unused variable ‘h’ [-Wunused-variable] int n,i,j,h,ma,aa,ab,mi; ^ user.cpp:17:17: warning: unused variable ‘ma’ [-Wunused-variable] int n,i,j,h,ma,aa,ab,mi; ^ user.cpp:17:26: warning: unused variable ‘mi’ [-Wunused-variable] int n,i,j,h,ma,aa,ab,mi; ^ user.cpp:15:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("trapez.in","r",stdin); ^ user.cpp:16:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("trapez.out","w",stdout); ^ user.cpp:19:19: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&n); ^ user.cpp:22:38: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d",&v[i].a,&v[i].b); ^