[P3812][模板]线性基

#include<cstdio>
#include<cstring>
#include<algorithm>
#include<cstdlib>
#include<iostream>
#include<cmath>
using namespace std;
typedef long long ll;
const int MAX_BASE=63;
ll base[64],a[60],n;
void getbase(){
  for(int i=1;i<=n;i++){
      for(int j=MAX_BASE;j>=0;j--){
          if(a[i]>>j){
              if(!base[j]){
                base[j]=a[i];
                break;
              }
              a[i]^=base[j];
          }
      }
  }
}

ll query_max(){
  ll ans=0;
  for(int i=MAX_BASE;i>=0;i--){
      if((base[i]^ans)>ans){
          ans=base[i]^ans;
      }
  }
  return ans;
}
int main(){
  scanf("%lld",&n);
  for(int i=1;i<=n;i++)scanf("%lld",&a[i]);
  getbase();
  ll ans=query_max();
  printf("%lld\n",ans);
}