// Problem: C. 或
// Contest: undefined - NOIP2024训练赛 13
// URL: http://noi.ac/contest/1165/problem/2481
// Memory Limit: 1024 MB
// Time Limit: 1000 ms
// 
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#include<bits/stdc++.h>
//#define int long long
#define fi first
#define se second
#define PII pair<int, int>

using namespace std;

const int N = 2e5 + 10, M = 1e6 + 10, mod = 1e9 + 7, INF = 0x3f3f3f3f;

int n, m, q, k, x, ans;
int s[N], dp[N];

vector<int> e[N];

signed main()
{
	ios::sync_with_stdio(0), cin.tie(0), cout.tie(0);
	cin >> n >> k >> x;	
	for(int i = 1; i <= n; i ++) cin >> s[i];
	sort(s + 1, s + n + 1); m = s[n];
	for(int i = 1; i <= k; i ++) m = m * x;
	for(int i = 1; i < n; i ++) ans |= s[i];
	ans |= m;
	cout << ans << '\n'; 
	return 0;
}