#include <bits/stdc++.h>
#include <atcoder/all>
using namespace std;
using namespace atcoder;
using ll=long long;

int main()
{
    int n;
    ll k;
    cin>>n>>k;
    vector<ll> a(n);
    for(int i=0;i<n;i++)cin>>a[i];
    sort(a.begin(),a.end());
    int cnt=0;
    for(int i=0;i<n;i++)if(a[i]<=k)cnt++;
    int cnt2=0;
    for(int i=cnt;i<n;i++)if(a[i]%2==0)cnt2++;
    ll ans=0;
    for(int i=cnt-1;i>=0;i-=2)ans+=a[i];
    if((cnt+cnt2)&1){
        ans+=(n-cnt-cnt2+1)/2;
        for(int i=cnt;i<n;i++)ans+=a[i]/2;
    }else{
        ans+=(n-cnt-cnt2)/2;
        for(int i=cnt;i<n;i++)ans+=a[i]/2;
    }
    cout<<ans<<endl;

    return 0;
}