线性基模板

const int N = 51;
ll a[N], p[101] = { 0 };
void get_lb(ll x) {
    for (int i = 63; i >= 0; i--) {
        if (x & (1LL << i)) {
            if (!p[i]) {
                p[i] = x;
                break;
            }
            else {
                x ^= p[i];
            }
        }
    }
}

洛谷p3812

#include<bits/stdc++.h>
#define ll long long
using namespace std;
const int N = 51;
ll a[N], p[101] = { 0 };
void get_lb(ll x) {
    for (int i = 63; i >= 0; i--) {
        if (x & (1LL << i)) {
            if (!p[i]) {
                p[i] = x;
                break;
            }
            else {
                x ^= p[i];
            }
        }
    }
}
int main()
{
    ll n;
    cin >> n;
    for (int i = 0; i < n; i++) {
        cin >> a[i];
        get_lb(a[i]);
    }
    ll ans = 0;
    for (int i = 63; i > 0; i--) {
        if (p[i] && (ans ^ p[i]) > ans) {
            ans ^= p[i];
        }
    }
    cout << ans << endl;
}