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Two Sets CodeForces - 468B

cati contains medium 位置 must print note sets turn

Little X has n distinct integers: p1,?p2,?...,?pn. He wants to divide all of them into two sets A and B. The following two conditions must be satisfied:

  • If number x belongs to set A, then number a?-?x must also belong to set A.
  • If number x belongs to set B, then number b?-?x must also belong to set B
    .

Help Little X divide the numbers into two sets or determine that it‘s impossible.

Input

The first line contains three space-separated integers n,?a,?b (1?≤?n?≤?105; 1?≤?a,?b?≤?109). The next line contains n space-separated distinct integers p1,?p2,?...,?pn (1?≤?pi?≤?109).

Output

If there is a way to divide the numbers into two sets, then print "YES" in the first line. Then print n

integers: b1,?b2,?...,?bn (bi equals either 0, or 1), describing the division. If bi equals to 0, then pi belongs to set A, otherwise it belongs to set B.

If it‘s impossible, print "NO" (without the quotes).

Example

Input
4 5 9
2 3 4 5
Output
YES
0 0 1 1
Input
3 3 4
1 2 4
Output
NO

Note

It‘s OK if all the numbers are in the same set, and the other one is empty.

增加一個案列:

4 10 16

4 6 10 12

題解:哇,被坑慘了。用二分搜索調了好久才發現有些情況解決不了,比如a-x和b-x同時存在時,不能直接確定放在那個位置。後面看了

別人的題解(http://www.cnblogs.com/zhien-aa/p/6726862.html),才知道用並查集管理。

 1 #include<bits/stdc++.h>
 2 using namespace std;
 3 
 4 const int maxn=1e5+5; 
 5 
 6 int n,a,b;
 7 int F[maxn],num[maxn];
 8 
 9 int Find(int x){
10     if(x==F[x]) return F[x];
11     return F[x]=Find(F[x]);
12 }
13 
14 int main()
15 {   while(cin>>n>>a>>b){
16         map<int,int> p;
17         for(int i=1;i<=n+2;i++) F[i]=i;
18         for(int i=1;i<=n;i++){
19             cin>>num[i];
20             p[num[i]]=i;
21         }
22         int temp;
23         for(int i=1;i<=n;i++){
24             temp=Find(i);
25             if(p[a-num[i]]) F[temp]=Find(p[a-num[i]]);
26             else F[temp]=Find(n+1);
27             temp=Find(i);
28             if(p[b-num[i]]) F[temp]=Find(p[b-num[i]]);
29             else F[temp]=Find(n+2);
30         }
31         if(Find(n+1)==Find(n+2)) cout<<"NO"<<endl;
32         else{
33             cout<<"YES"<<endl;
34             for(int i=1;i<=n;i++) printf("%d%c",Find(i)==Find(n+1),i==n?\n: ); 
35         }
36     }
37 } 

Two Sets CodeForces - 468B