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

int main(){
	ll N, K;
	cin >> N >> K;
	vector<ll> A(N);
	for (auto &x : A) cin >> x;
	sort(A.begin(), A.end(), [&](int l, int r){
		if (max(l, r) <= K) return l > r;
		if (r <= K) return false;
		if (l <= K) return true;
		return (r % 2 == 1) && (l % 2 == 0);
	});
	ll ans = 0;
	for (int i = 0; i < N; i++){
		if (A[i] <= K){
			if (i % 2 == 0) ans += A[i];
		}
		else{
			ans += (A[i] + i % 2) / 2;
		}
	}
	cout << ans << "\n";
}