335 - Processing MX Records

[pem3v78]

Hello,

Could you provide test data (extreme conditions would be helpful also) ?

Thanks

[junbin]

I am trying to solve q335 (Processing MX Records) and I keep getting WA for some reasons.

I've tried handling cases where there are wildcards in the first string and so on, but still no success.

Can anyone with AC please answer some of my queries?

1) Is the judge case-sensitive?
2) If the judge is case-sensitive, should we print the result as upper case, lower case or original case?
3) If there are multiple choices with the same priorities, how do we determine which one to choose?
4) If there's a record for mail.a.com and *.a.com and *.com and *, which one do we choose?



If it is not too inconvenient, can someone just run the following test data through their AC program please?

test data:

Code: Select all

31
a.com  0  b.com
a.com  0  c.com
a.com  0  d.com
y.com  0  G.com
Z.com  0  e.com
mail.b.edu 0 server1.com
*.b.edu 0 server2.com
*.edu 0 server3.com
*il.b.edu 0 server4.com
*edu 0 server5.com
mail.b.org 5 server1.org
*.b.org 4 server2.org
*.org 3 server3.org
*il.b.org 2 server4.org
*org 1 server5.org
*net 1 server5.net
*il.b.net 2 server4.net
*.net 3 server3.net
*.b.net 4 server2.net
mail.b.net 5 server1.net
*ws 5 server5.ws
*il.b.ws 4 server4.ws
*.ws 3 server3.ws
*.b.ws 2 server2.ws
mail.b.ws 1 server1.ws
mail.b.biz 1 server1.biz
*il.b.biz 2 server2.biz
*.b.biz 3 server3.biz
*.biz 4 server4.biz
*biz 5 server5.biz
* 100 catchall
A a.com
D c.com
A a.com
D b.com
A a.com
U c.com
A a.com
D d.com
A a.com
A A.com
A z.com
A y.com
A Y.com
A mail.b.edu
A grail.b.edu
A home.b.edu
A c.edu
A cedu
A mail.b.org
A grail.b.org
A home.b.org
A c.org
A corg
A mail.b.net
A grail.b.net
A home.b.net
A c.net
A cnet
A mail.b.ws
A grail.b.ws
A home.b.ws
A c.ws
A cws
A mail.b.biz
A grail.b.biz
A home.b.biz
A c.biz
A cbiz
A g.com.sg
A microsoft.com
A uva.edu.es
A onlinejudge.uva.es
X

My output:

Code: Select all

a.com => d.com
a.com => d.com
a.com => d.com
a.com => d.com
a.com => c.com
a.com => c.com
z.com => e.com
y.com => G.com
y.com => G.com
mail.b.edu => server1.com
grail.b.edu => server4.com
home.b.edu => server2.com
c.edu => server3.com
cedu => server5.com
mail.b.org => server5.org
grail.b.org => server5.org
home.b.org => server5.org
c.org => server5.org
corg => server5.org
mail.b.net => server5.net
grail.b.net => server5.net
home.b.net => server5.net
c.net => server5.net
cnet => server5.net
mail.b.ws => server1.ws
grail.b.ws => server2.ws
home.b.ws => server2.ws
c.ws => server3.ws
cws => server5.ws
mail.b.biz => server1.biz
grail.b.biz => server2.biz
home.b.biz => server3.biz
c.biz => server4.biz
cbiz => server5.biz
g.com.sg => catchall
microsoft.com => catchall
uva.edu.es => catchall
onlinejudge.uva.es => catchall

[sjn]

i think there is no test data with multiple choices.

[sjn]

my ACed program ran out with the following

Code: Select all

a.com => 
a.com => 
a.com => d.com
a.com => c.com
a.com => c.com
A.com => catchall
z.com => catchall
y.com => G.com
Y.com => catchall
mail.b.edu => server1.com
grail.b.edu => server2.com
home.b.edu => server2.com
c.edu => server3.com
cedu => server5.com
mail.b.org => server5.org
grail.b.org => server5.org
home.b.org => server5.org
c.org => server5.org
corg => server5.org
mail.b.net => server5.net
grail.b.net => server5.net
home.b.net => server5.net
c.net => server5.net
cnet => server5.net
mail.b.ws => server1.ws
grail.b.ws => server2.ws
home.b.ws => server2.ws
c.ws => server3.ws
cws => server5.ws
mail.b.biz => server1.biz
grail.b.biz => server2.biz
home.b.biz => server3.biz
c.biz => server4.biz
cbiz => server5.biz
g.com.sg => catchall
microsoft.com => catchall
uva.edu.es => catchall
onlinejudge.uva.es => catchall

It looks funny

[junbin]

I managed to get AC'ed. Apparently, my code was correct.. I just had to remove the case-insensitive bit... and then change the input.

I think they are putting tabs in the input because when I did manual parsing of the input, I skipped all the spaces and got WA.. but when I use gets and sscanf, I get AC.

[Dejarik]

I'm also getting Wrong Answer, but i cannot understand your correct outputs. The input of the example posted by junbin starts saying:

Code: Select all

a.com  0  b.com 
a.com  0  c.com 
a.com  0  d.com 
y.com  0  G.com 
Z.com  0  e.com

So, why the first lines writted by your programs tells this one in junbin's version:

Code: Select all

a.com => d.com 
a.com => d.com 
a.com => d.com 
a.com => d.com 
a.com => c.com 
a.com => c.com

and this one in sjn's version:

Code: Select all

a.com => 
a.com => 
a.com => d.com 
a.com => c.com 
a.com => c.com

My output is the following one. I don't understand why a.com is redirected to d.com or (blank) in your versions if the first MX records redirects this machine to b.com (like my versions' output)

Thanks in advance!

Joan

Code: Select all

a.com => b.com
a.com => d.com
a.com => catchall
a.com => c.com
a.com => 
A.com => 
z.com => 
y.com => G.com
Y.com => 
mail.b.edu => server1.com
grail.b.edu => server2.com
home.b.edu => server3.com
c.edu => server5.com
cedu => 
mail.b.org => server5.org
grail.b.org => server4.org
home.b.org => server3.org
c.org => 
corg => 
mail.b.net => server5.net
grail.b.net => server4.net
home.b.net => server3.net
c.net => 
cnet => 
mail.b.ws => server1.ws
grail.b.ws => server2.ws
home.b.ws => server3.ws
c.ws => server5.ws
cws => 
mail.b.biz => server1.biz
grail.b.biz => server2.biz
home.b.biz => server3.biz
c.biz => server4.biz
cbiz => server5.biz
g.com.sg => 
microsoft.com => 
uva.edu.es => 
onlinejudge.uva.es =>

[junbin]

If I remmeber right, there's no case where multiple answers are possible
eg

a.com 0 b.com
a.com 0 c.com


but anyway, a quick look at the answers:

A a.com
D c.com
A a.com
D b.com
A a.com
U c.com
A a.com
D d.com
A a.com


You can see that for the last A a.com, c.com is up.. so a.com should redirect to c.com

[Dejarik]

so you are saying me that

Code: Select all

2
a.com 0 machineA.com
a.com 0 machineB.com
A    a.com
X

will output this one:

Code: Select all

a.com => machineA.com

or

Code: Select all

a.com => machineB.com

??


Thanks in advance, Joan

[junbin]

There won't be a case where there's a possibility of ambiguity.. so there won't be a :

x a y
x a z


where x y z are server names and a is a prioirty number

[Kadaver]

Good morning,

I tried to solve this problem, but I'm still getting WAs. I have changed my program according to information from this forum, but still it isn't working. I tried to run my program on the input from this page and the output was:

a.com => b.com
a.com => b.com
a.com => d.com
a.com => c.com
a.com => c.com
A.com => catchall
z.com => catchall
y.com => G.com
Y.com => catchall
mail.b.edu => server1.com
grail.b.edu => server4.com
home.b.edu => server2.com
c.edu => server3.com
cedu => server5.com
mail.b.org => server5.org
grail.b.org => server5.org
home.b.org => server5.org
c.org => server5.org
corg => server5.org
mail.b.net => server5.net
grail.b.net => server5.net
home.b.net => server5.net
c.net => server5.net
cnet => server5.net
mail.b.ws => server1.ws
grail.b.ws => server2.ws
home.b.ws => server2.ws
c.ws => server3.ws
cws => server5.ws
mail.b.biz => server1.biz
grail.b.biz => server2.biz
home.b.biz => server3.biz
c.biz => server4.biz
cbiz => server5.biz
g.com.sg => catchall
microsoft.com => catchall
uva.edu.es => catchall
onlinejudge.uva.es => catchall

It is simillar to sjn's version, but still, I can't convince the judge, that this is right. I wrote it in Java and I skipped all whitespaces in reading the input (not only space characters), but it didn't help.

I'm really hopeless here. Can you help me please?

Thanks in advance...

Kadaver

[minskcity]

Would anybody tell me what can be possibly wrong with my code? I print lexicographically smallest web site if there are multiple choices. I check "If the first field is not present" by using isspace()...

Code: Select all

#include <cctype>
#include <algorithm>
#include <iostream>
#include <string>
#include <sstream>
#include <map>
#include <set>
#include <vector>
using namespace std;

map < string, vector < pair < int, string > > > data, datax;

int main(){
    
    string s, a, b;
    int n, p; cin >> n; getline(cin, s);
    while(n-- && getline(cin, s)){
	istringstream sin(s);
	if(isspace(s[0])) sin >> p >> b;
	else sin >> a >> p >> b;
	if(a[0] == '*') datax[a.substr(1)].push_back(make_pair(p, b));
	else data[a].push_back(make_pair(p, b));
    }
    
    set < string > down;
    while(cin >> a >> b && a != "X")
	if(a == "D") down.insert(b);
	else if(a == "U") down.erase(b);
	else{
	    cout << b << " => ";
	    vector < pair < int, string > > all;
	    if(data.count(b)) all = data[b];
	    for(int i = 0; i <= (int)b.size(); i++)
		if(datax.count(b.substr(i))){
		    vector < pair < int, string > > &add = datax[b.substr(i)];
		    for(int i = 0; i < (int)add.size(); i++)
			all.push_back(add[i]);
		}
	    sort(all.begin(), all.end());
	    string ans = "";
	    for(int i = 0; i < (int)all.size(); i++)
		if(!down.count(all[i].second)){
		    ans = all[i].second;
		    break;
		}
	    if(ans.size()) cout << ans;
	    cout << endl;
	}
    

    return 0;
}

[igorsk]

The input seems to contain commands different from D, U, A and X. When I change your solution so that it ignores bad commands, it gets ACC.

I had the same problem with my code - I was throwing an exception on bad input and kept getting RE.

[metaphysis]

I dont't think so, my AC solution assumes that there is no other commands rather than U, D, A, X.