/*  Erica N  */
#include <bits/stdc++.h>
using namespace std;
#define pb push_back
#define mp make_pair
#define int long long
#define ull unsigned long long
#define pii pair<int, int>
#define ps second
#define pf first
#define itn int
#define rd read()
int read(){
    int xx = 0, ff = 1;char ch = getchar();
    while (ch < '0' || ch > '9') {if (ch == '-')ff = -1; ch = getchar();}
    while (ch >= '0' && ch <= '9')xx = xx * 10 + (ch - '0'), ch = getchar();
    return xx * ff;
}
// void write(int out) {
// 	if (out < 0)
// 		putchar('-'), out = -out;
// 	if (out > 9)
// 		write(out / 10);
// 	putchar(out % 10 + '0');
// }
#define cdbg(x...) do { cerr << #x << " -> "; err(x); } while (0)
void err() { cerr << endl; }
template<template<typename...> class T, typename t, typename... A>
void err(T<t> a, A... x) { for (auto v: a) cerr << v << ' '; err(x...); }
template<typename T, typename... A>
void err(T a, A... x) { cerr << a << ' '; err(x...); }


const int N = 3e5 + 5;
const int INF = 1e18;
const int M = 1e7;
const int MOD = 1e9 + 7;

int a[N];

signed main() {
    // freopen(".in","r",stdin);
    // freopen(".out","w",stdout);



    int n=rd,K=rd,x=rd;
    for(int i=1;i<=n;i++){
        a[i]=rd;
    }

    if(x==1){
        int ans=0;
        for(int i=1;i<=n;i++){
            ans|=a[i];
        }
        cout<<ans<<endl;

    }else{
        int mx=0;
        for(int i=1;i<=n;i++){
            if(a[mx]<a[i])mx=i;
        }

        while(K--){
            a[mx]=a[mx]*x;
        }
        int ans=0;
        for(int i=1;i<=n;i++){
            ans|=a[i];
        }
        cout<<ans<<endl;

        
    }


}