#include<bits/stdc++.h>
using namespace std;
const int N=1010,M=40;
int n,m,a[N],f[N][M],ans;
int main() 
{ 
	cin>>n>>m;
	for(int i=1;i<=n;i++)
	{
		cin>>a[i];
		a[i]%=2;
	}
	for(int j=0;j<=m;j++)
	{
		for(int i=1;i<=n;i++)
		{
			if(j)
			{
				f[i][j]=max(f[i-1][j]+(j%2!=a[i]),f[i-1][j-1]+(j%2==a[i]));
			}
			else
			{
				f[i][j]=f[i-1][j]+(j%2!=a[i]);
			}
		}
	}
	for(int i=0;i<=m;i++)
	{
		ans=max(ans,f[n][i]);
	}
	cout<<ans;
	return 0;
}