Eroare de compilare: user.c:4:16: warning: useless storage class specifier in empty declaration [enabled by default] typedef struct P { double x,y; }; ^ user.c:5:1: error: unknown type name ‘P’ P v[100005]; ^ In file included from user.c:1:0: user.c: In function ‘main’: user.c:13:36: error: request for member ‘x’ in something not a structure or union assert(scanf("%lf%lf",&v[i].x,&v[i].y)==2); ^ user.c:13:44: error: request for member ‘y’ in something not a structure or union assert(scanf("%lf%lf",&v[i].x,&v[i].y)==2); ^ user.c:14:31: error: request for member ‘x’ in something not a structure or union assert(-10000000<=v[i].x&&v[i].x<=10000000); ^ user.c:14:39: error: request for member ‘x’ in something not a structure or union assert(-10000000<=v[i].x&&v[i].x<=10000000); ^ user.c:15:31: error: request for member ‘y’ in something not a structure or union assert(-10000000<=v[i].y&&v[i].y<=10000000); ^ user.c:15:39: error: request for member ‘y’ in something not a structure or union assert(-10000000<=v[i].y&&v[i].y<=10000000); ^ user.c:18:17: error: request for member ‘x’ in something not a structure or union s+=(v[i].x*v[i+1].y-v[i+1].x*v[i].y); ^ user.c:18:26: error: request for member ‘y’ in something not a structure or union s+=(v[i].x*v[i+1].y-v[i+1].x*v[i].y); ^ user.c:18:35: error: request for member ‘x’ in something not a structure or union s+=(v[i].x*v[i+1].y-v[i+1].x*v[i].y); ^ user.c:18:42: error: request for member ‘y’ in something not a structure or union s+=(v[i].x*v[i+1].y-v[i+1].x*v[i].y); ^