> 把cmp改成这样就过了。
> 
> int cmp(const void* a, const void* b){
> 	
> 	struct rect *c = (struct rect *)a;
> 	struct rect *d = (struct rect *)b;
> 	if(c->x1 != d->x1) return (d->x1)-(c->x1);
> 	else if( c->x2 != d->x2 ) return (c->x2)-(d->x2);
> 	else if( c->y1 != d->y1 ) return (d->y1)-(c->y1);
> 	else  return (c->y2)-(d->y2);
> )

顶一个，开始没注意到