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

const int mxn = 105;

int n, k, a[mxn];
int f(int x) {
	return (x <= k) ? x : x / 2;
}
struct node {
	int delta, id;
} b[mxn];

int main() {
	cin >> n >> k;
	for (int i = 1; i <= n; ++i) cin >> a[i];
	for (int i = 1; i <= n; ++i) {
		b[i] = { f(a[i]) - (a[i] - f(a[i])), i };
	}
	sort(b + 1, b + n + 1, [&](const node &lhs, const node &rhs) {
		return lhs.delta > rhs.delta;
	});
	LL ans = 0;
	for (int i = 1; i <= n; ++i) {
		int p = b[i].id;
		if (i & 1) ans += f(a[p]);
		else ans += a[p] - f(a[p]);
	}
	printf("%lld\n", ans);
	return 0;
}