Problem Description

ZCC loves playing cards. He has n magical cards and each has a number on it. He wants to choose k cards and place them around in any order to form a circle. He can choose any several 

consecutive cards the number of which is m(1<=m<=k) to play a magic. The magic is simple that ZCC can get a number x=a1⊕a2...⊕am, which ai means the number on the ith card he chooses. He can play the magic infinite times, but 

once he begin to play the magic, he can’t change anything in the card circle including the order.

ZCC has a lucky number L. ZCC want to obtain the number L~R by using one card circle. And if he can get other numbers which aren’t in the range [L,R], it doesn’t matter. Help him to find the maximal R.

 

Input

The input contains several test cases.The first line in each case contains three integers n, k and L(k≤n≤20,1≤k≤6,1≤L≤100). The next line contains n numbers means the numbers on the n cards. The ith number a[i] satisfies 1≤a[i]≤100.

You can assume that all the test case generated randomly.

 

Output

For each test case, output the maximal number R. And if L can’t be obtained, output 0.

 

Sample Input

4 3 1 2 3 4 5

 

Sample Output

7

Hint

⊕ means xor

用全排列的方法来做。这我一開始还真没想到

#include 
       
        #include 
        
         #include 
         
          using namespace std;int n,k,l,r;int vis[500],a[500],tem[500],s[500];void set(int len,int sum){    vis[sum] = 1;    if(len == k)        return ;    set(len+1,sum^tem[len]);    set(len+1,sum);}int check(){    memset(vis,0,sizeof(vis));    set(0,0);    for(int i = l; i<=r; i++)        if(!vis[i])            return 0;    return 1;}void solve(){    if(!check()) return ;    int i,j;    for(i = 0; i