Compilare: user.cpp: In function ‘int main()’: user.cpp:37:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=1;i<=n;i++) ^ user.cpp:38:40: warning: format ‘%d’ expects argument of type ‘int*’, but argument 2 has type ‘long int*’ [-Wformat=] scanf("%d %d",&a[i].x,&a[i].y); ^ user.cpp:38:40: warning: format ‘%d’ expects argument of type ‘int*’, but argument 3 has type ‘long int*’ [-Wformat=] user.cpp:44:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=1;i<=n;i++){ ^ user.cpp:50:27: warning: format ‘%d’ expects argument of type ‘int’, but argument 2 has type ‘long int’ [-Wformat=] printf("%d\n",area-b/2+1); ^ user.cpp:33:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("copaci.in","r",stdin); ^ user.cpp:34:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("copaci.out","w",stdout); ^ user.cpp:36:19: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&n); ^ user.cpp:38:41: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d",&a[i].x,&a[i].y); ^