#include <bits/stdc++.h>   using namespace std;   int main() {     int mas[105] = {0};     int n;     scanf( %d  , &n);     int res = -1;     int resl = -1;     for (int i = 0; i < n; i++) scanf( %d  , &mas[i]);     for (int i = 0; i < n; i++) {       int len = 0;       int mest = 0;       for (int j = i; j < n; j++) {         len++;         mest ^= mas[j];         if (mest > res) {           res = mest;           resl = len;         }       }     }     cout << res;     return 0;   }   