题解

# include <bits/stdc++.h>
typedef unsigned long long ull;

#define getchar getchar_unlocked()
#define psbc push_back
#define v vector
#define for1 for(i = 0;i<n;i++)
#define be(x) x.begin(),x.end()

using  namespace  std ;
const int MX = 1e5;
int i,j,k;
int r(){
    int x = 0,f = 1;
    char c = getchar;
    while(c<'0'||c>'9'){if(c=='-') f = -1;c = getchar;}
    while(c>='0'&&c<='9') x = (x<<1)+(x<<3)+(c^(3<<4)),c = getchar;
    return x*f;
}
int  main ( )
{
    int n = r();
    v<ull>arr(n);
    for(i = 0;i<n;i++){
        arr[i] = r();
    }
    v<ull>bas(60);
    for(auto num:arr){
        ull cur = num;
        for(i = 59;i>=0;i--){
            if(cur&(1ULL<<i)){
                if(bas[i]==0){
                    bas[i] = cur;
                    break;
                }
                else{
                    cur ^= bas[i];
                }
            }
        }
    }
    ull mxr = 0;
    for(i = 59;i>=0;i--){
        if(bas[i]==0) continue;
        if((mxr^bas[i])>mxr){
            mxr ^= bas[i];
        }
    }
    cout<<mxr;
    return  0;
}