gistfile1.txt

const readline = require('readline')
const rl = readline.createInterface({
    input: process.stdin,
    output: process.stdout
});
const int_bits = 32;
let lalle = 0;
rl.on('line',(line)=>{
    
    let nums = line.split(' ');
    if(lalle%2 === 0){
        arr_length = parseInt(nums[0])
        if(arr_length === 0){
            return 0;
        }
    }else{
        nums = nums.map((elem)=> parseInt(elem))
        console.log(maxXorSum2(nums,nums.length))
    }
    lalle++
})

function maxXorSum2 (set,n){
    let index = 0;  
    for (let i = int_bits - 1; i >= 0; i--)  
    { 
    let maxInd = index; 
    let maxEle = -2147483648; 
    for (let j = index; j < n; j++) { 
          
 
        if ((set[j] & (1 << i)) != 0 && set[j] > maxEle) 
        { 
        maxEle = set[j]; 
        maxInd = j; 
        } 
    } 
  

    if (maxEle == -2147483648) 
        continue; 
  

    let temp = set[index]; 
    set[index] = set[maxInd]; 
    set[maxInd] = temp; 

    maxInd = index; 
  

    for (let j = 0; j < n; j++) { 
          
      
        if (j != maxInd && (set[j] & (1 << i)) != 0) 
        set[j] = set[j] ^ set[maxInd]; 
    } 
  
 
    index++; 
    } 
  
  
    let res = 0; 
    for (let i = 0; i < n; i++) 
        res ^= set[i]; 
    
    return res; 
}