ENG  RUSTimus Online Judge
Online Judge
Problems
Authors
Online contests
About Online Judge
Frequently asked questions
Site news
Webboard
Links
Problem set
Submit solution
Judge status
Guide
Register
Update your info
Authors ranklist
Current contest
Scheduled contests
Past contests
Rules
back to board

Discussion of Problem 1019. Line Painting

Why my prog crash?Who can help me?Thanks a lot.
Posted by odp 17 Feb 2005 11:38
I get crash(access_violation) at test #9 many times.

#include "stdio.h"

struct wp
{
 long a,b;
 char c; /*color*/
 struct wp *next;
}head;

main()
{
 long a,b,s;
 char c;
 int i,n;
 struct wp *p,*q,*k;
 head.a=0;
 head.b=1000000000;
 head.c='w';
 head.next=NULL;
 scanf("%d",&n);
 for(i=0;i<n;i++)
 {
  scanf("%ld%ld",&a,&b);
  c=0;
  while(c!='b' && c!='w') c=getchar();
  for(p=&head;p!=NULL;p=p->next) if(p->a<=a && p->b>=a) break;
  for(q=&head;q!=NULL;q=q->next) if(q->a<=b && q->b>=b) break;
  if(q->next!=NULL && q->next->a==b) q=q->next;
  for(k=p->next;k!=NULL && k!=q && k!=q->next;k=k->next) delete k;
  if(p->c==c && q->c==c)
  {
   p->b=q->b;
   p->next=q->next;
   if(p!=q) delete q;
   continue;
  }
  if(p==q)
  {
   if(p->a==a && p->b==b) {p->c=c;continue;}
   if(p->a==a)
   {
    k=p->next;
    p->next=new struct wp;
    p->next->next=k;
    p->next->a=b;
    p->next->b=p->b;
    p->next->c=p->c;
    p->c=c;
    p->b=b;
    continue;
   }
   if(p->b==b)
   {
    k=p->next;
    p->next=new struct wp;
    p->next->next=k;
    p->next->a=a;
    p->next->b=b;
    p->next->c=c;
    p->b=a;
    continue;
   }
   k=p->next;
   p->next=new struct wp;
   p->next->next=new struct wp;
   q=p->next->next;
   q->next=k;
   q->b=p->b;
   q->a=b;
   q->c=p->c;
   p->next->a=a;
   p->next->b=b;
   p->next->c=c;
   p->b=a;
   continue;
  }
  if(p->a==a) p->c=c;
  if(q->b==b) q->c=c;
  if(p->c==c) a=p->a;
  if(q->c==c) b=q->b;
  if(p->c!=c && q->c!=c)
  {
   p->b=a;
   q->a=b;
   p->next=new struct wp;
   p->next->a=a;
   p->next->b=b;
   p->next->c=c;
   p->next->next=q;
   continue;
  }
  if(p->c==c && q->c!=c)
  {
   p->next=q;
   p->b=b;
   q->a=b;
   continue;
  }
  p->next=q;
  p->b=a;
  q->a=a;
 }
 s=-1;
 for(k=&head;k!=NULL;k=k->next)
 if(k->b-k->a>s && k->c=='w')
 {
  s=k->b-k->a;
  a=k->a;
  b=k->b;
 }
 printf("%ld %ld\n",a,b);
 return 0;
}
Re: Why my prog crash?Who can help me?Thanks a lot.
Posted by odp 18 Feb 2005 13:18
I removed all "delete" and got AC.But I don't know why?
Re: Why my prog crash?Who can help me?Thanks a lot.
Posted by odp 19 Feb 2005 11:10
Sorry,I know why now.