Dear All,

I have solved the problem using dynamic programming where dp[i][0] indicates not to include the current element i into the set and dp[i][1] indicates to include the current element into the set. Here is my code:

#include<bits/stdc++.h>
#include<math.h>
using namespace std;

long long int a[100001];

long long int dp[100002][2];

int main()
{
    long int n,i;
    scanf("%ld",&n);
    for ( i = 1 ; i <= n ; i++ ){
        scanf("%lld",&a[i]);
    }
    //memset(dp, 0, sizeof(dp[0][0]) * 2 * 100002);
    for( i = n ; i >= 1 ; i--){
        dp[i][0] = max(dp[i+1][0] ^ 0 , dp[i+1][1] ^ 0);
        dp[i][1] = max(dp[i+1][0] ^ a[i],dp[i+1][1] ^ a[i]);
    }
    dp[0][0] = max(dp[1][0]^0,dp[1][1]^0);
    printf("%lld",dp[0][0]);
}

I am getting a wrong answer even though the test cases I tried are giving the correct ouput. I checked the constraints as well and the data types are correct. It is a very short code. Could someone please help me?

Thank you.