#include<iostream>
#include<cstdio>
#include<cstring>
#include<algorithm>
#include<vector>
#include<queue>
#include<stack>
#include<deque>
#include<set>
#include<map>
#include<cmath>
#define rint int
#define mem(a,b) memset(a,b,sizeof a)
#define lowbit(x) (x&-x)
#define debug(a,b) cout<<"line"<<__LINE__<<":"<<a<<" = "<<b<<endl;
#define eb emplace_back
#define pb push_back
#define read raed
#define int long long
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
typedef pair<int,int> pii;
const int inf=0x3f3f3f3f;
const ll INF=1e18;
const int N=108;
template<typename T> 
void read(T &x){
    x=0;int f=1;char c=getchar();
    while(!isdigit(c)){if(c=='-') f=-1;c=getchar();}
    while(isdigit(c)){x=x*10+c-'0';c=getchar();}
    x*=f;
}
template<typename T,typename ... Args>
void read(T &x, Args &... y){read(x);read(y...);}
int n,k,ans;
struct p{int x,v;} a[N];
inline int val(int x){
    if(x<=k) return x;
    if(x%2) return -1;
    return 0;
}
signed main(){
    read(n,k);
    for(rint i=1,x;i<=n;i++) read(x),a[i]={x,val(x)},ans+=x;
    sort(a+1,a+n+1,[](p a,p b){return a.v>b.v;});
    for(rint i=1;i<=n;i++) ans+=((i%2)?1:-1)*a[i].v;
    cout<<ans/2<<endl;
	return 0;
}