#include<cstdio>
#include<string.h>
#include<algorithm>
using namespace std;
const int M1 = 555;
const int INF = 111111111;
int N,K;
int ans;
int w[M1][M1];//w[i][j] is the number of white horses in the last stable when the first i horses were placed in 1st j stables with minimum unhappiness
int b[M1][M1];//b[i][j] is the number of black horses in the last stable when the first i horses were placed in 1st j stables with minimum unhappiness
int f[M1][M1];//f[i][j] means the minimum unhappiness when the first i horses were placed in 1st j stables
//function: f[i][j] = min(f[i-1][j-1],f[i-1][j]+w[i-1][j] or b[i-1][j]);

int main()
{
    memset(w,0,sizeof(w));
    memset(b,0,sizeof(b));
    memset(f,0,sizeof(f));
    scanf("%d%d",&N,&K);
    for(int i=0;i!=M1;++i)
    {   for(int j=i+1;j!=M1;++j)
            f[i][j] = INF;
        f[i][0] = INF;
    }
    int tmp;
    scanf("%d",&tmp);
    if(tmp) ++b[1][1];
    else ++w[1][1];
    f[1][1] = 0;
    for(int i=2;i<=N;++i)
    {   scanf("%d",&tmp);
        for(int j=1;j<=min(i,K);++j)
        {   f[i][j] = f[i-1][j-1];
            b[i][j] = 0;
            w[i][j] = 0;
            if(tmp)
            {   ++b[i][j];
                if(f[i-1][j]+w[i-1][j]<f[i][j])
                {   b[i][j] = b[i-1][j]+1; w[i][j] = w[i-1][j];
                    f[i][j] = f[i-1][j]+w[i-1][j];
                }
            }
            else
            {   ++w[i][j];
                if(f[i-1][j]+b[i-1][j]<f[i][j])
                {   b[i][j] = b[i-1][j]; w[i][j] = w[i-1][j]+1;
                    f[i][j] = f[i-1][j]+b[i-1][j];
                }
            }
        }
    }
    ans = f[N][K];
    printf("%d",ans);
    return 0;
}